Philosophy quotes organized

This post is a collection of quotes about philosophy. There are about 1,700 quotes listed below, organized into 62 categories. This post will be a work in progress as I continue to organize and collect quotes. The painting above is by Wassily Kandinsky titled Murnau, Dorfstrasse (1908).

Although I don't agree with every quote listed below, I have included anything I think is interesting. The categories listed below don't have strict boundaries and most quotes work for multiple categories. Despite the inherent subjectiveness, I tried my best to organize the quotes as accurately as possible. Here is a list of the categories:

1. Abstraction, 2. Artificial intelligence, 3. Beliefs, 4. Causation, 5. Cogito, 6. Complexity, 7. Consciousness and self, 8. Contradiction, 9. Description, 10. Distractions, 11. Emergence, 12. Error, 13. Expansion of knowledge, 14. Experiments, 15. Free will, 16. Grammar, 17. History, 18. Holism, 19. Infinity, 20. Intuition, 21. Inventions, 22. Literature, 23. Logic 24. Mathematics a priori, 25. Mathematics catalogue, 26. Mathematics everything, 27. Mathematics exact, 28. Mathematics geometry, 29. Mathematics innovation, 30. Mathematics numbers, 31. Mathematical patterns, 32. Measurement, 33. Meditation, 34. Memory, 35. Metaphysics, 36. Neuroscience, 37. Ockham's razor, 38. Patterns, 39. Physics, 40. Pictures, 41. Probability, 42. Questions, 43. Quotation, 44. Reason, 45. Reductionism, 46. Relativism, 47. Rhetoric, 48. Sense, 49. Skepticism, 50. Sociology and politics, 51. Subjective language, 52. Symbols, 53. Systematic analysis, 54. Thought, 55. Time, 56. Truth, 57. Understanding, 58. Web of beliefs, 59. Word confusion, 60. Word creation, 61. Word meaning, 62. Word use

1. Abstraction

Eric Temple Bell:
"Abstractness, sometimes hurled as a reproach at mathematics, is its chief glory and its surest title to practical usefulness." (The Development of Mathematics, 1940)

George Boole:
"Of the many forms of false culture, a premature converse with abstractions is perhaps the most likely to prove fatal to the growth of a masculine vigor of intellect." (A Treatise on Differential Equations, 1859)

Tobias Dantzig:
"Between the philosopher's attitude towards the issue of reality and that of the mathematician there is this essential difference: for the philosopher the issue is paramount; the mathematician's love for reality is purely platonic." (Number: The Language of Science, 1930)

Leonard Euler:
"Although to penetrate into the intimate mysteries of nature and thence to learn the true causes of phenomena is not allowed to us, nevertheless, it can happen that a certain fictive hypothesis may suffice for explaining many phenomena." (A Conjecture about the Nature of Air, 1780)

David Hume:
"Nothing is more dangerous to reason than the flights of the imagination, and nothing has been the occasion of more mistakes among philosophers." (A Treatise  of Human Nature, 1739)

C. Wright Mills:
"The capacity to shuttle between levels of abstraction, with ease and clarity, is a signal mark of the imaginative and systematic thinker." (The Social Imagination, 1959)

Leonardo da Vinci
"Human subtlety... will never devise an invention more beautiful, more simple or more direct than does nature, because in her inventions nothing is lacking, and nothing is superfluous." (Quoted by The Notebooks of Leonardo da Vinci by Rudolf Flesch)

William Whewell:
"Again, we find the Greek philosophers applying themselves to extract their dogmas from the most general and abstract notions which they could detect." (History of the Inductive Sciences, 1837)

2. Artificial intelligence

Howard Aiken:
"The desire to economize time and mental effort in arithmetical computations, and to eliminate human liability to error is probably as old as the science of arithmetic itself." (1937, Proposed Automatic Calculating Machine)

Daniel Dennett:
"But this seems to uncover an enormous puzzle of just what, if anything, consciousness is for. Can a conscious entity do anything for itself that an unconscious (but clearly wired up) simulation of that entity couldn't do for itself." (The Evolution of Consciousness, 1998)

Richard Feynman:
"What often happens is that an engineer has an idea of how the brain works (in his opinion) and then designs a machine that behaves that way. This new machine may in fact work very well. But I must warn you that that doesn't tell us anything about how the brain actually works nor is it necessary to every really know that, in order to make a computer very capable." (The Pleasure of Finding Things Out, 1999)

Richard Feynman:
"It is therefore not necessary to imitate the behavior of nature in detail in order to engineer a device which can in many respects surpass nature's abilities." (The Pleasure of Finding Things Out, 1999)

Stephen Hawking:
"The development of full artificial intelligence could spell the end of the human race. We cannot quite know what will happen if a machine exceeds our own intelligence, so we can't know if we'll be infinitely helped by it, or ignored by it and sidelined, or conceivably destroyed by it." (BBC interview, 2014)

Gina Kolata:
"A computer program written by researchers at Argonne National Library in Illinois has come up with a major mathematical proof that would have been called creative if a human had though of it. In doing so, the computer has for the first time, got a toehold into pure mathematics, a field described by its practitioners as more of an art form than a science." (With Major Math Proof, Brute Computers Show Flash of Reasoning Power, 1996)

Marvin Minsky:
"Computer languages of the future will be more concerned with goals and less with procedures specified by the programmer." (Turing Award Lecture, 1969)

Theodore Roszak:
"Can those who believe the computer is 'an embodiment of mind' really not tell the difference between so poorly a caricature and the true original?" (The Gendered Atom, 1999)

John Searle:
"I will argue that in the literal sense the programmed computer, understand what the car and the adding machine understand, namely exactly nothing." (Minds, Brains and Programs, 1980)

Alan Turing:
"A computer would deserve to be called intelligent if it could deceive a human into believing that it was human." (AZQuotes.com)

Alan Turing:
"If one wants to make a machine mimic the behaviour of the human computer in some complex operation one has to ask him how it is done, and then translate the answer into the form of an instruction table. Constructing instruction tables is usually described as 'programming'." (Computing Machinery and Intelligence, 1950)

Alan Turing:
"We may hope that machines will eventually compete with men in all purely intellectual fields. But which are the best ones to start with? Many people think that a very abstract activity, like the playing of chess, would be best. It can also be maintained that it is best to provide the machine with the best sense organs that money can buy, and then teach it to understand and speak English." (AZQuotes.com)

Alan Turing:
"It seems probable that once the machine thinking method had started it would not take long to outstrip our feeble powers... They would be able to converse with each other to sharpen their wits. As some stage therefore, we should have to expect the machines to take control." (Goodreads.com)

Alan Turing:
"I believe that at the end of the century the use of words and general educated opinion will have altered so much that one will be able to speak of machines thinking without expecting to be contradicted." (Computing Machinery and Intelligence, 1950)

Alfred North Whitehead:
"Civilization advances by extending the number of important operations which we can perform without thinking about them." (An Introduction to Mathematics, 1911)

Alfred North Whitehead:
"By relieving the brain of all unnecessary work, a good notation sets it free to concentrate on more advanced problems, and in effect increases the mental power of the race." (An Introduction to Mathematics, 1911)

3. Beliefs

Aristotle:
"He who wishes to learn must believe." (Sophistical Refutations)

Claude Bernard:
"Theories are only verified hypotheses, verified by more or less numerous facts. Those verified by the most facts are the best, but even then they are never final, never to be absolutely believed." (Introduction à l'Étude de la Médecine Expérimentale, 1865)

Max Born:
"There are two objectionable types of believers: those who believe the incredible and those who believe that 'belief' must be discarded and replaced by 'the scientific method'." (Natural Philosophy of Cause and Chance, 1964)

Gottlob Frege:
"A judgement for me is not the mere grasping of a thought, but the admission of its truth." (On Sense and Reference, 1892)

Gottlob Frege:
"Facts, facts, facts' cries the scientist if he wants to emphasize the necessity of a firm foundation for science. What is a fact? A fact is a thought that is true. But the scientist will surely not recognize something which depends on men's varying states of mind to be the firm foundation of science." (The thought: A logical inquiry, 1956 posthumous)

David Hume:
"I say, then, that belief is nothing but a more vivid, lively, forcible, firm, steady conception of an object, than what the imagination alone is ever able to attain." (An Enquiry Concerning Human Understanding, 1748)

William James:
"That nature will follow tomorrow the same laws that she follows today is, they admit, a truth which no man can know; but in the interest of cognition as well as of action we must postulate or assume it." (The Sentiment of Rationality, 1882)

Dennis Lindley:
"Uncertainty is a personal matter; it is not the uncertainty but your uncertainty." (Understanding Uncertainty, 2006)

Friedrich Nietzsche:
"There are no facts. Only interpretations" (Notebooks 1886-1887)

Henri Poincare:
"To doubt everything or to believe everything are two equally convenient solutions; both dispense with the necessity of reflection." (Science and Hypothesis, 1901)

Willard van Orman Quine:
"Believing is a disposition. We could tire ourselves out thinking, if we put our minds to it, but believing takes no toll." (Goodreads.com)

Thucydides:
"On the whole, however, the conclusions I have drawn from the proofs quoted may, I believe, safely be relied on. Assuredly they will not be disturbed either by the compositions of the chroniclers that are attractive at truth's expense." (History of the Peloponnesian War)

4. Causation

Avicenna:
"The knowledge of anything, since all things have causes, is not acquired or complete unless it is known by its causes." (On Medicine)

A. J. Ayer:
"As Hume conclusively showed, no one event intrinsically points to any other. We infer the existence of events which are not actually observing with the help of the general principle. But these principles must be obtained inductively." (Language, Truth and Logic, 1936)

Claude Bernard:
"Indeed, proof that a given condition always precedes or accompanies a phenomenon does not warrant concluding with certainty that a given condition is the immediate cause of that phenomenon. It must still be established that when this condition is removed, the phenomenon will no longer appear." (Introduction à l'Étude de la Médecine Expérimentale, 1865)

Joseph Fourier:
"Primary causes are unknown to us; but are subject to simple and constant laws, which may be discovered by observation, the study of them being the object of natural philosophy. (The Analytical Theory of Heat, 1878)

Louis Daguerre:
"The daguerreotype is not merely an instrument which serves to draw Nature; on the contrary it is a chemical and physical process which gives her the power to reproduce herself." (Art-Quotes.com)

Werner Heisenberg:
"Causality can only explain later events by earlier events, but it can never explain the beginning." (Physic and Philosophy, 1958)

Thomas Hobbes:
"...when we see how anything comes about, upon what causes, and by what manner; when the like causes come into our power, we see how to make it produce the like effects." (The Leviathan, 1651)

Thomas Hobbes:
"Science is the knowledge of Consequences, and dependence of one fact upon another: by which, out of that we can presently do, we know how to do something else when we will, or the like, another time..." (The Leviathan, 1651)

David Hume:
"The cause must be prior to the effect." (A Treatise of Human Nature, 1739)

Pierre-Simon Laplace:
"Imaginary causes have gradually receded with the widening bounds of knowledge and disappear entirely before sound philosophy which sees in them only the expression of our ignorance of the true causes." (Philosophical Essays on Probabilities, 1812)

Albertus Magnus:
"Natural science does not consist in ratifying what others have said, but in seeking the causes of phenomena." (Quoted in The Middle Ages by Morris Bishop)

Ovid:
"The cause is hidden but the result is known." (Meta Morphoses)

Charles Sanders Peirce:
"...these general ideas are not mere words, nor do they consists in this, that certain concrete facts will every time happen under certain descriptions of conditions; but they are just as much, or rather far more, living realities than the feelings themselves out of which they are concreted." (The Law of Mind, 1892)

Henri Poincare:
"If all the parts of the universe are interchained in a certain measure, any one phenomenon will not be the effect of a single cause, but the resultant of causes infinitely numerous; it is, one often says, the consequence of the state of the universe the moment before." (The Value of Science, 1905)

Aldolphe Quetelet:
"It may be seen, in my work, that the course which I have adopted is that followed by the natural philosopher, in order to grasp the laws that regulate the material world. By the seizure of facts, I seek to rise to an appreciation of the causes whence the spring." (A Treatise on Man and the Development of his Faculties, 1842)

Aldolphe Quetelet:
"...that so long as the same causes exist, we must expect a repetition of the same effects." (A Treatise on Man and the Development of his Faculties, 1842)

Bertrand Russell:
"The law of causality, I believe, like much that passes muster among philosophers, is a relic of a bygone age, surviving like the monarchy, only because it is erroneously supposed to do no harm." (Mysticism and Logic and Other Essays, 1918)

William Thomson:
"In general the actions which we see ever taking place around us are complex, or due to the simultaneous action of many causes." (Treatise on Natural Philosophy with Peter Guthrie Tait, 1867)

5. Cogito

A. J. Ayer:
"'I exist' does not follow from 'there is a thought now'. The fact is that a thought occurs at a given moment does not entail that any other thought has occurred at any other moment, still less that there has occurred at any other moment, still less that there has occurred a series of thoughts sufficient to constitute a single self. As Hume conclusively showed, no one event intrinsically points to any other." (Language, Truth and Logic, 1936)

Rene Descartes:
"I think, therefore I am." (Le Discours de la Methode, 1637)

Sam Harris:
"Consciousness is the one thing in this universe that cannot be an illusion." (Waking Up, 2014)

David Hume:
"All sentiment is right; because sentiment has a reference to nothing beyond itself and is always real, wherever a man is conscious of it." (Essays, Moral, Political and Literary, 1741)

William James:
"There is but one indefectivel certain truth, and that is the truth that pyrrhonistic skepticism itself leaves standing - the truth that the present phenomenon of consciousness exists." (The Will to Believe, 1897)

Peter Machamer, J. E. McGuire:
"Our analysis of the cogito should make clear that for Descartes its validity is an immediate intuition of a truth contained in an idea grasped in an instant, an intuition that contains no temporal successiveness." (Descartes Changing Mind, 2009)

Jean-Paul Sartre:
"My thought is me: that's why I can't stop. I exist because I think... and I can't prevent myself from thinking." (Nausea, 1938)

6. Complexity

W. Brian Arthur:
"Complexity is looking at interacting elements and asking how they form patterns and how the patterns unfold. Its important to point out that the patterns may never be finished. They're open ended." (Quoted in Coming from Your Inner Self by Joseph Jaworski, 1999)

Francis Bacon:
"It cannot be that axioms established by argumentation should avail for the discovery of new works, since the subtlety of nature is greater many times over than the subtlety of argument." (Novum Organum, 1620)

Francis Bacon:
"Since my logic aims to teach and instruct the understanding, not that it may with the slender tendrils of the mind snatch at an lay hold of abstract notions (as the common logic does), but that it may in very truth dissect nature and discover the virtues and actions of bodies, with their laws as determined in matter..." (Novum Organum, 1620)

Eric Temple Bell:
"Nearly always it is the recondite and complicated which is elaborated first; and it is only when some relatively unsophisticated mind attacks a problem that its deep simplicity is revealed." (The development of mathematics, 1940)

Ronald Fisher:
"I believe that no one who is familiar, either with mathematical advances in other fields, or with the range of special biological conditions to be considered, would ever conceive that everything could be summed up in a single mathematical formula, however complex." (The evolutionary modification of genetic phenomena, 1932)

Michael C. Jackson:
"The classification of a system as complex or simple will depend upon the observer of the sytem and upon the purpose they have for considering the system." (Towards a System of Systems Methodologies, 1984)

William James:
"The bigger the unit you deal with, the hollower, the more brutal, the more mendacious is the life displayed." (Letter to Henry Whitman, 1899)

William James:
"Reduced to their most pregnant difference, empiricism means the habit of explaining wholes by parts, and rationalism means the habit of explaining parts by wholes." (A Pluralistic Universe, 1909)

George Henry Lewes:
"Artists brood over the chaos of their suggestions, and thus shape them into creations." (The Principles of Success in Literature, 1865)

George Henry Lewes:
"Although the mind instinctively rejects all needless complexity, we shall greatly err if we fail to recognize the fact, that what the mind recoils from is not the complexity, but the needlessness." (The Principles of Success in Literature, 1865)

Gregor Mendel:
"That no generally applicable law of the formulation and development of hybrids has yet been successfully formulated can hardly astonish anyone who is acquainted with the extent of the task and who can appreciate the difficulties with which experiments of this kind have to contend." (Experiments on Plant Hybrids, 1865)

Dmitri Mendeleev:
"It is the function of science to discover the existence of a general reign of order in nature and to fin the causes governing this order." (AZquotes.com)

John von Neumann
"Truth.. is much too complicated to allow anything but approximations." (Quoted in The Works of the Mind by R. B. Heywood)

Charles Sanders Peirce:
"All the evolution we know of proceeds from the vague to the definite." (Collected Papers)

Henri Poincare:
"If we study the history of science we see happen two inverse phenomena... Sometimes simplicity hides under complex appearances; sometimes it is the simplicity which is apparent, and which disguises extremely complicated realities." (Science and Hypothesis, 1901)

Karl Popper:
"Science may be described as the art of systematic over-simplification..." (The Open Universe : An Argument for Indeterminism, 1992)

L. K. Samuels:
"The more complexity, the more unpredictability and therefore the more uncontrollability. You cannot control what you cannot predict." (Speech at the Libertopia Festival, 2013)

L. K. Samuels:
"In fact, many chaologists and physicists posit that universal laws are more flexible than first realized, and less rigid - operating in spurts, jumps, instead of like clockwork. Chaos prevails over rules an systems because it has the freedom of infinite complexity over the known, unknown, and the unknowable." (2013)

George Santayana:
"Chaos is name for any order that produces confusion on our minds." (Quoted in Wisdom for the Soul by Larry Chang)

Alfred North Whitehead:
"We think in generalities, but we live in detail. To make the past live, we must perceive it in detail in addition to thinking of it in generalities." (The Education of an English Man in the Atlantic Monthly, 1926)

Alfred North Whitehead:
"The ultimate metaphysical principle is the advance from disjunction to conjunction, creating a novel entity other than the entities given in disjunction." (Process and Reality: An Essay in Cosmology, 1929)

Friedrich Wohler:
"At this time organic chemistry can drive one completely crazy. It seems to me like a primeval tropical jungle, full of the most remarkable things, an amazing thicket, without escape or end into which one would not dare to enter." (Quoted in The Way of Synthesis by Thomas Hudlicky)

7. Consciousness and self

Aristotle:
"Whether if soul did not exist time would exist or not, is a question that may fairly be asked; for if there cannot be someone to count there cannot be anything can be counted, so that evidently there cannot be number for number is either what has been, or what can counted." (Quoted in Merleau-Ponty Vivant by Martin Dillon)

Simone de Beauvoir:
"Let us try to assume our fundamental ambiguity. It is in the knowledge of the genuine conditions of our life that we must draw our strength to live and our reason for acting." (The Ethics of Ambiguity, 1947)

David Bohm:
"Then there is the further question of what is the relationship of thinking to reality? As careful attention shows, thought itself is an actual process of movement." (Wholeness and the Implicate Order, 1980)

David Bohm:
"I would say that in my scientific and philosophical work, my main concern has been with understanding the nature of reality in general and of consciousness in particular as a coherent whole, which is never statistic or complete but which is an unending process of movement and unfoldment..." (Wholeness and the Implicate Order, 1980)

David Bohm:
"Deep down the consciousness of mankind is one. This is a virtual certainty because even in the vacuum matter is one; and if we don't see this it's because we are blinding ourselves to it." (Quoted in Towards a Theory of Transpersonal Decision-making in Human Systems by Joseph Riggio)

David Bohm:
"The point about dialectic is the ultimate identity of the universal and the individual. The individual is universal and the universal is the individual." (Quoted in Dialogues with Scientists and Sages by Renee Weber)

Santiago Ramón y Cajal:
"The history of civilization proves beyond doubt just how sterile the repeated attempts of metaphysics to guess at nature's laws have been. Instead, there is every reason to believe that when the human intellect ignores reality and concentrates within, it can no longer explain the simplest inner workings of life' s machinery or of the world around us." (1897, Advice for a Young Investigator)

Thomas Carlyle:
"Nay, in every epoch of the world, the great event, parent of all others, is it not the arrival of a thinker in the world?" (Heros and Hero Worship, 1840)

David Chalmers:

"Why doesn't all this information-processing go on 'in the dark', free of any inner feel? ...We know that conscious experience does arise when these functions are performed, but the very fact that it arises is the central mystery." (Facing Up to the Problem of Consciousness, 1995)

Charles Darwin:
"As I was lead to keep in my study during many months worms in pots filled with earth, I became interested in them, and wished to learn how far they acted consciously and how much mental power they displayed." (The Formation of Vegetable Mould through the Action of Worms, 1881)

Charles Darwin:
"In this case, therefore, the worms judged with a considerable degree of correctness how best to draw the withered leaved of this foreign plant into their burrows; notwithstanding that they had to depart from the usual habit of avoiding the foot-stalk." (The Formation of Vegetable Mould through the Action of Worms, 1881)

Charles Darwin:
"The lower animals, like man, manifestly feel pleasure and pain, happiness and misery... Even insects play together..." (The Descent of Man, 1871)

Giles Deleuze:
"Something in the world forces us to think. This something is an object not of recognition but of a fundamental encounter." (Goodreads.com)

Jacques Derrida:
"...the first question of philosophy is: What is it to be? What is 'being'? The question of being is itself always already divided between who and what. Is 'being' someone or something?" (Goodreads.com)

Jacques Derrida:
"At the end of Being and Nothingness... Being in-itself and Being for-itself were of Being; and this totality of beings, in which they were effected, itself was linked up to itself, relating and appearing to itself, by means of the essential project of human-reality." (Margins of Philosophy, 1972)

Rene Descartes:
"The entire arrangement of the things to which the minds's eye must turn so that we can discover some truth." (Rules for the Direction of the Mind, 1628)

Rene Descartes:

"But what is a thinking thing? It is a thing that doubts, understands, affirms, denies, wills, refuses, and that also imagines and senses." (Meditations on First Philosophy, 1641)

Michel Foucault:
"The painter is turning his eyes towards us only in so far as we happen to occupy the same position as his subject. We, the spectators, are an additional factor." (The Order of Things: An Archaeology of the Human Sciences, 1970)

Michel Foucault:
"We are observing ourselves being observed by the painter, and made visible to his eyes by the same light that enables us to see him. And just as we are about to apprehend ourselves, transcribed by his hand as though in a mirror, we find that we can in fact apprehend nothing of that mirror but its lusterless back. The other side of a psyche." (The Order of Things: An Archaeology of the Human Sciences, 1970)

Sigmund Freud:
"The ego represents what we call reason and sanity, in contrast to the id which contains passions." (The Ego and the Id, 1923)

Sigmund Freud:
"The poor ego has a still harder time of it; it has to serve three harsh masters, and it has to do its best to reconcile the claims and demands of all three.. the three tyrants are the external world, the superego and the id." (New Introductory Lectures of Psychoanalysis, 1933)

Sigmund Freud:
"The ego is not master in its own house." (A Difficulty in the Path of Psychoanalysis, 1917)

Northrop Frye:
"At the level of ordinary consciousness, the individual man is the center of everything, surrounded on all sides by what he isn't." (The Educated Imagination, 1963)

Martin Heidegger:
"We ourselves are the entities to be analyzed." (Being and Time, 1927)

Martin Heidegger:
"Everyone is the other, and no one is himself. The they, which supplies the answer to the who of everyday Dasein, is the nobody to whom every Dasein has always surrendered itself, in its being-among-one-another." (Being and Time, 1927)

Martin Heidegger:
"Language is the house of the truth of Being." (Letter on Humanism, 1947)

Martin Heidegger:
"Death is the possibility of the absolute impossibility of Dasein." (Being and Time, 1927)

Edmund Husserl:
"To begin with, we put the proposition: pure phenomenology is the science of pure consciousness." (Brainyquote.com)

William James:
"Consciousness, then, does not appear itself chopped up in bits... a 'river' or a 'stream' are the metaphors by which it is most naturally described." (The Principles of Psychology, 1890)

William James:
"As we take, in fact, a general view of the wonderful stream of out consciousness, what strikes us first is this different pace of it's parts. Like a bird's life, it seems to be made of an alteration of flights and perching." (The Principles of Psychology, 1890)

Carl Jung:
"It is the ego that serves to light up the entire system, allowing it to become conscious and thus to be realized." (Man and His Symbols, 1964)

Carl Jung:
"We can never legitimately cut loose from our archetypal foundations unless we are prepared to pay the price of a neurosis..." (Quoted by J. B. Priestly in Times Literary Supplement)

Carl Jung:
"Every civilized human being, whatever his conscious development, is still an archaic man at the deeper levels of his psyche." (Modern Man in Search of a Soul, 1933)

Soren Kierkegaard:
"One must learn to know oneself before knowing anything else. Not until a person has inwardly understood himself and then sees the course he is to take does his life gain peace and meaning." (The Journals of Søren Kierkegaard, 1835)

Soren Kierkegaard:
"But in the heart of nature, where a person, free from life's often nauseating air, breathes more freely, here the soul opens willingly to every noble impression. Here one comes out as nature's master, but he also feels that something higher is manifested in nature, something he must bow down before; he feels a need to surrender to this power that rules it all." (The Journals of Søren Kierkegaard, 1835)

Soren Kierkegaard:
"Oh, can I really believe the poet's tales, that when one first sees the object of one's love, one imagines one has seen her long ago, that all love like all knowledge is remembrance, that love too has its prophecies in the individual." (On Regine Olsen, 1939)

Gottfried Leibniz:

"Moreover, we must confess that the perception, and what depends on it, is inexplicable in terms of mechanical reasons, that is, through shapes and motions." (Monadology, 1714)

Thomas Merton:
"Art enables us to find ourselves and lose ourselves at the same time." (Brainy Quote)

Michel de Montaigne:
"It is a thorny undertaking, and more so than it seems, to follow a movement so wandering as that of our mind, to penetrate the opaque depths of its innermost folds, to pick out and immobilize the innumerable flutterings that agitate it." (Essais, 1580)

Michel de Montaigne:
"I have seen no more evident monstrosity and miracle in the world than myself." (Essais, 1580)

Alan Moore:
"Consciousness is unquantifiable, a ghost in the machine, barely considered real at all, though in a sense this flickering mosaic of awareness is the only true reality that we can ever know." (What is reality)

Parmenides:
"For it is the same thing that can be thought and that can be." (Quoted in Enneads by Plotinus)

Parmenides:
"For to be aware and to be are the same." (Of Nature)

Blaise Pascal:
"In order to enter into a real knowledge of your condition, consider it in this image: A man was cast by a tempest upon an unknown island, the inhabitants of which were in trouble to find their king, who was lost; and having a strong resemblance both in form and face to this king, he was taken for him, and acknowledged in this capacity by all the people." (The Art of Persuasion)

Charles Sanders Peirce:
"Consciousness must essentially cover an interval of time; for if it did not, we could gain no knowledge of time, and not merely no veracious cognition of it, but no conception whatever." (The Law of Mind, 1892)

Charles Sanders Peirce:
"Qualities of feeling show myriad-fold variety, far beyond what the psychologists admit." (Pragmatism and Pragmaticism, 1903)

Charles Sanders Peirce:
"The recognition by one person of another's personality takes place by means to some extent identical to the means by which he is conscious of his own personality." (The Law of Mind, 1892)

Charles Sanders Peirce:
"That artist's observational power is what is most wanted in the study of phenomenology." (Pragmatism and Pragmaticism, 1903)

Charles Sanders Peirce:
"Our whole past experience is continually in our consciousness, though most of it sunk to a great depth of dimness. I think of consciousness as a bottomless lake, whose waters seem transparent yet into which we can clearly see but a little way." (Collected Papers)

Roger Penrose:
"Years ago, I wrote a book called the emperor's new mind and that book was describing a point of view I had about consciousness and why it was not something that comes about from complicated calculations so we are not exactly computers." (Wikiquote)

Roger Penrose:
"Every one of our conscious brains is woven from subtle physical ingredients that somehow enable us to take advantage of the profound organization of our mathematically underpinned universe - so that we, in turn, are capable of some direct access..." (Shadows of the Mind: A Search for the Missing Science of Consciousness, 1994)

Roger Penrose:
"How do our feelings of conscious awareness - of happiness, pain, love, aesthetic sensibility, will, understanding, etc, fit into such a computational picture?" (Brainyquote.com)

Bernhard Riemann:
"It is absurd to assume that upon the rigid earth-crust the organic originated from the inorganic." (Gesammelte Mathematische Werke, 1876)

Bernhard Riemann:
"The souls of perished creatures shall... form the elements of the soul-life of earth." (Gesammelte Mathematische Werke, 1876)

Bertrand Russell:
"Man is essentially a dreamer wakened sometimes for a moment by some peculiarly obtrusive element in the outer world, but lapse again quickly into the happy somnolence of imagination." (Sceptical Essays, 1928)

Gilbert Ryle:
"The dogma of the Ghost in the Machine... maintains that there exist both bodies and minds; that there occur physical processes and mental processes; that there are mechanical causes of corporeal movements and mental causes of corporeal movements. I shall argue that these and other analogous conjunctions are absurd." (The Concept of Mind, 1949)

Gilbert Ryle:
"I shall often speak of it, with deliberate abusiveness, as 'the dogma of the Ghost in the Machine'. I hope to prove that it is entirely false, and false not in detail but in principle... It is, namely, a category mistake. It represents the facts of mental life as if they belonged to one logical type or category (or range of types or categories) when they actually belong to another." (The Concept of Mind, 1949)

Arthur Leonard Schawlow:
"Dead is when chemists take over the subject." (Quoted in Biographical Memoirs by Steven Chu and Charles Townes)

Friedrich Schelling:
"If there is to be any philosophy at all, this contradiction must be resolved - and the solution of this problem, or answer to the question: how can we think both of presentations as conforming to objects, and objects as conforming to presentations? Is it, not the first, but the highest task of transcendental philosophy?" (System of Transcendental Philosophy, 1800)

Friedrich Schelling:
"It is easy to see that this problem can be solved neither in theoretical nor in practical philosophy, but only in a higher discipline, which is the link that combines [presentations and objects], and neither theoretical nor practical, but both at once." (System of Transcendental Philosophy, 1800)

Friedrich Schelling:
"How both the objective world accommodates to presentations in us, and presentations in us to the objective world, is unintelligible unless between the two worlds, the ideal and the real, there exists a pre-determined harmony. But this latter is itself unthinkable unless the activity, whereby the objective world, is produced, is at bottom identical with that which expresses itself in volition, and vice versa." (System of Transcendental Philosophy, 1800)

Erwin Schrodinger:
"Consciousness cannot be accounted for in physical terms. For consciousness is absolutely fundamental. It cannot be account for in terms of anything else." (Quoted in The Observer, 1931)

Erwin Schrodinger:
"Consciousness is never experienced in the plural, only in the singular." (Matter and Mind, 1956)

Erwin Schrodinger:
"Vedanta teaches that consciousness is singular, all happenings are played out in one universal consciousness and there is not multiplicity of selves." (My View of the World, 1961)

Erwin Schrodinger:
"The observing mind is not a physical system, it cannot interact with any physical system." (Nature and the Greeks, 1954)

John Searle:
"The ascription of an unconscious intentional phenomenon to a system implies that the phenomenon is in principle accessible to consciousness." (Consciousness, Explanation Inversion and Cognitive Science, 1990)

John Searle:
"Where conscious subjectivity is concerned, there is no distinction between the observation and the thing observed." (The Rediscovery of the Mind, 1992)

Thales:
"The most difficult thing in life is to know yourself." (Quoted in Many Thoughts of Many Minds by Henry Southgate)

Alfred Russel Wallace:
"To say that mind is a product or function of protoplasm, or of its molecular changes, is to use words to which we can attach no clear conception. You cannot have, in the whole, what does not exist in any of the parts; and those who argue thus should put forth a definite conception of matter, with clearly enunciated properties, and show, that the necessary result of a certain complex arrangement of the elements or atoms of that matter, will be the production of self-consciousness." (Considerations to the Theory of Natural Selection, 1870)

Alfred Russel Wallace:
"There is, I conceive, no contradiction in believing that mind is at once the cause of matter and of the development of individualized human minds through the agency of matter." (Harmony of Spiritualism and Science, 1885)

Simone Weil:
"Although people seem to be unaware of it today, the development of the faculty of attention forms the real object and almost the sole interest of studies." (Reflections on the right Use of School Studies with a View to the Love of God)

Simone Weil:
"We should have with each person the relationship of one conception of the universe to another conception of the universe, and not to a part of the universe." (Gravity and Grace, 1948)

Ludwig Wittgenstein:
"Knowledge is in the end based on acknowledgement." (Quoted in Hitchcock as Philosopher by Robert Yanal)

8. Contradiction

Averroes:
"Two truths cannot contradict one another." (Goodreads.com)

David Bohm:
"What is essential here is the presence of the spirit of dialogue, which is in short, the ability to hold many points of view in suspension, along with a primary interest in the creation of common meaning." (Science Order and Creativity, 1987 with David Peat)

Louis de Broglie:
"Two seemingly incompatible conceptions can each represent an aspect of the truth... They may serve in turn to represent the facts without ever entering into direct conflict." (Dialectica Volume 2, 1948)

Giles Deleuze:
"Paradox is the pathos or the passion of philosophy." (Goodreads.com)

Enrico Fermi:
"There are two possible outcomes: if the result confirms the hypothesis, then you've made a measurement. If the result is contrary to the hypothesis, then you've made a discovery." (Wikiquote)

Paul Feyerabend:
"Early Chinese thinkers had taken variety at face value. They had favored diversification and collected anomalies instead of trying to explain them away." (Conquest of Abundance, 2001 posthumous)

Linus Pauling:
"I keep looking for some... problem where someone has made an observation that doesn't fit into my picture of the universe. If it doesn't fit in, then I find some way of fitting in it." (Interview with George B. Kauffman and Laurie M. Kauffman, 1994)

Edward Teller:
"We must learn to live with contradictions, because they lead to deeper and more effective understanding." (Science and Morality, 1998)

9. Descriptions

Aristotle:
"Of things said without any combination, each signifies either substance or quantity or qualification or a relative or where or when or being-in-a-position or having or doing or being affected." (Categories)

Ilhan Basgoz:
"Digression bridges the gap, making the unknown known, irrational rational, obscure clear, incredible credible." (Quoted in Metalanguage by Yael Mashler)

Walter Benjamin:
"Counsel woven into the fabric of life is wisdom. The art of storytelling is reaching its end because the epic side of truth, wisdom is dying out." (The Storyteller)

Peter Berger:
"...it is safe to say that mythology represents the most archaic form of universe-maintenance..." (The Social Cohesion of Reality, 1966)

Georg W. F. Hegel:
"Reading the morning newspaper is the realist's morning prayer. One orients one's attitude toward the world either by God or by what the world is. The former gives as much security as the latter, in that one knows how one stands." (Miscellaneous writings of G.W.F. Hegel by Jon Bartley Stewart)

Adam Horowitz, Edward Kitsis:
"What do you think stories are for? These stories are classics. There's a reason we all know them. They're a way for us to deal with our world. A world that doesn't always make sense." (Once Upon a Time, 2011)

Franz Kafka:
"The whole visible world is perhaps nothing more than the rationalization of a man who wants to find peace for a moment. An attempt to falsify the actuality of knowledge, to regard knowledge as a goal still to be reached. " (Parables and Paradoxes, posthumous)

John Maynard Keynes:
"I have now reached a stage in the argument where I have to choose between being too definite or being too vague. If I set forth a concrete proposal in all its particulars, I expose myself to a hundred criticisms on points not essential to the principle of the plan. If I go further in the use of figures for illustration, I am involved more and more in guess-work; and I run the risk of getting the reader bogged in details which may be inaccurate and could certainly be amended without injury to the main fabric. Yet if I restrict myself to generalities, I do not give the reader enough to bite on; and am in fact shirking the issue, since the size, the order of magnitude, of the factors involved is not an irrelevant detail." (How to Pay for the War, 1940)

George Henry Lewes:
"...it is in the selection of the characteristic details that the artistic power is manifested." (The Principles of Success in Literature, 1865)

Ernst Mach:
"In reality, the law always contains less than the fact itself, because it does not reproduce the fact as a whole but only in that aspect of it which is important for us, the rest being intentionally or from necessity omitted." (The Economical Nature of Physical Inquiry, 1898)

Albertus Magnus

"Nature must be the foundation and model of science; thus Art works according to Nature in everything it can. Therefore, it is necessary that the Artist follows Nature and operates according to her." (De Vegetabilibus)

Moses Mendelssohn:
"The analysis of concepts is for the understanding nothing more than what the magnifying glass is for sight." (Brainy Quote)

John von Neumann:
"The sciences do not try to explain, they hardly even try to interpret, they mainly make models. By a model is meant a mathematical construct which, with the addition of certain verbal interpretations, describes observed phenomena." (Method in the Physical Sciences, 1955)

Plato:
"All that is said by us can only be imitation and representation." (Critas)

Karl Popper
"Science must begin with myths, and with the criticism of myths." (Conjectures and Refutations, 1963)

Willard van Orman Quine:
"It is within science itself, and not some prior philosophy, that reality is to be identified and described." (Theories and Things, 1981)

Anatol Rapoport:
"A fundamental value in the scientific outlook is concerned with the best available map of reality." (Science and the Goals of Man, 1950)

Bernhard Riemann:
"The completion or amelioration of the concept-system forms the 'explanation' of the unexpected observation. By this process our comprehension of nature becomes gradually always more complete and assured but at the same time recedes even farther behind the surface of phenomena." (Gesammelte Mathematische Werke, 1876)

Rajneesh:
"In fact, all explanations are against God because explanation demystifies existence. Existence is a mystery, and one should accept it as a mystery and not pretend to have any explanation." (Never Born, Never Died, 2005 posthumous)

Patrick Rothfuss:
"That's why stories appeal to us. They give us the clarity and simplicity our real lives lack." (The Name of the Wind, 2007)

Muriel Rukeyser:
"The universe is made of stories, not of atoms." (The Speed of Darkness, 1968)

J. D. Salinger:
"The trouble with me is, I like it when somebody digresses. It's more interesting and all... Oh sure! I like somebody to stick to the point and all. But I don't like them to stick too much to the point." (The Catcher in the Rye, 1951)

Simon Schama:
"Historians are left forever chasing shadows, painfully aware of their inability ever to reconstruct an ideal world in its completeness however thorough or revealing their documentation." (Dead Certainties, 1991)

Lawrence Sterne:
"Digressions, incontestably, are the sunshine; and they are the life, the soul of reading; take them out of this book for instance, you might as well take the book along with them." (The Life and Opinions of Tristram Shandy, Gentlemen)

Henry Fox Talbot:
"One advantage of the discovery of the Photographic Art will be, that it will enable us to introduce into our pictures a multitude of minute details which add to the truth and reality of the representation, but which no artist would take the trouble to faithfully copy from nature." (AZ Quotes)

Kenneth Waltz:
"Data, seeming facts, apparent associations - these are not certain knowledge of something. They may be puzzles that can one day be explained; they may be trivia that need not be explained at all." (Theory of International Politics, 1979)

Simone Weil:
"Science is voiceless; it is the scientists who talk." (Lectures on Philosophy, posthumous)

Ludwig Wittgenstein:
"Mine is the first and only world. I want to report the world as I found it." (Quoted in Wittgenstein: A Wonderful Life documentary)

Ludwig Wittgenstein:
"The world is the totality of facts, not things." (Tractatus Logico-Philosophicus, 1922)

Ludwig Wittgenstein:
"The limits of my language mean the limits of my world." (Tractatus Logico-Philosophicus, 1922)

Ludwig Wittgenstein:
"Every explanation is after all a hypothesis." (Philosophical Occasions, 1993 posthumous)

10. Distractions

Charles Beard
"When it is dark enough, you can see the stars." (Brainy Quote)

Boethius:
"By first recognizing false goods, you begin to escape the burden of their influence; then afterwards true goods may gain possession of your spirit." (The Consolation of Philosophy)

Giles Deleuze:
"So it's not a problem of getting people to express themselves but of providing little gaps of solitude and silence in which they might eventually find something to say." (Negotiations, 1990)

Paul Dirac
"The interpretation of quantum mechanics has been dealt with by many authors, and I do not want to discuss it here. I want to deal with more fundamental things." (The inadequacies of quantum field theory)

Herophilos (335-280 BC, physician):
"When health is absent, wisdom cannot reveal itself, art cannot become manifest, strength cannot be exerted, wealth is useless, and reason is powerless." (AZ Quotes)

Socrates

"The body is a source of endless trouble to us by reason of the mere requirement of food and is also liable to diseases which overtake and impede us in the search after truth: and by filling us so full of loves, and lusts, and fears, and fancies, and idols, and every sort of folly prevents our ever having, as people say, so much as a thought." (Phaedo)

Henry David Thoreau:

"I find it so difficult to dispose of the few facts which to me are significant, that I hesitate to burden my attention with those with are insignificant, which only a divine mind could illustrate. Such is for the most part, the news in newspapers and conversation. It is important to preserve the mind's chastity in this respect." (Life with Principles, 1863)

Edward Titchener
"Knowledge is the product of leisure. The members of a very primitive society have no time to amass knowledge; their days are fully occupied with the provision of the bare necessities of life." (An Outline of Psychology, 1916)

Charles Townes
"In many cases, people who win a Nobel prize, their work slows down after that because of the distractions. Yes, fame is rewarding, but it's a pity if it keeps you from doing the work you are good at." (Brainy Quote)

Alfred North Whitehead:
"Philosophy is the self-correction by consciousness of its own initial excess of subjectivity... the task of philosophy is to recover the totality obscured by the selection." (Process and Reality: An Essay in Cosmology, 1929)

E. O. Wilson:
"We are drowning in information, while starving for wisdom. The world henceforth will be run by synthesizers, people able to put together the right information at the right time, think critically about it, and make important choices wisely." (1998, Consilience: The Unity of Knowledge)

11. Emergence

Murray Gell-Mann:
"You don't need something more to get something more.That's what emergence means." (TED talk on the Beauty and Truth in Physics, 2007)

Michael C. Jackson:
"...the whole often seems to take on a form that is not recognizable from the parts." (Systems Thinking: Creative Holism for Managers, 2003)

Michael C. Jackson:
"There exists an alternative to reductionism for studying systems. This alternative is known as holism. Holism considers systems to be more than the sum of their parts. It is of course interested in the parts and particularly the networks of relationships between the parts, but primarily how they give rise to and sustain in existence the new entity that is the whole..." (Systems Thinking: Creative Holism for Managers, 2003)

Michael C. Jackson:
"Reductionism sees the parts as paramount and seeks to identify the parts, understand the parts and work up from an understanding of the parts to an understanding of the whole. The problem with this is that the whole often seems to take on a form that is not recognizable from the parts." (Systems Thinking: Creative Holism for Managers, 2003)

Sylvia Mader:
"Each biological organization builds upon the previous level and is more complex. Moving up the hierarchy, each level acquires new emergent properties that are determined by the interactions between individual parts." (Biology, 2010)

Parmenides:
"And it is all one to me. Where I am to being; for I shall return there again." (Of Nature)

Parmenides:
"[What exists] is now, all at once, one and continuous... Nor is it divisible, since it is all alike; nor is there any more or less of it in one place which might prevent it from holding together, but all is full of what is." (Of Nature)

Parmenides:
"How could what is perish? How could it have come to be? For if it came into being, it is not; nor is it if ever it is going to be. Thus coming into being is extinguished and destruction unknown." (Of Nature)

Maurice Merleau-Ponty:
"In reality all things are concretions of a setting..." (Phenomenology of Perception, 1945)

L. K. Samuels:
"Without this creative self-organizing force, the universe would be devoid of biological life, the birth of the stars and galaxies - everything we have come to know." (Chaos Gets a Bad Rap, 2015)

L. K. Samuels:
"In essence, chaos is a phase transition that gives spontaneous energy the means to achieve repetitive and structural order." (In Defense of Chaos, 2013)

L. K. Samuels:
"Order is not universal. In fact, many chaologists and physicists posit that universal laws are more flexible than first realized, and less rigid - operating in spurts, jumps and leaps, instead of like clockwork. Chaos prevails over rules and systems..." (In Defense of Chaos, 2013)

12. Error

Francis Bacon:
"Truth will sooner come out from error than from confusion." (Novum Organum, 1620)

David Hilbert:
"We can measure the importance of a scientific work by the number of earlier publications rendered superfluous by it." (Quoted in Mathematical Circles Revisited by Howard Eves, 1971)

David Hume:
"No conclusions can be more agreeable to skepticism than such as make discoveries concerning the weakness and narrow limits of human reason and capacity." (An Enquiry Concerning Human Understanding, 1748)

Montesquieu

"Nothing is a greater obstacle to our progress in knowledge, than a bad performance of a celebrated author; because, before we instruct we must begin with undeceiving." (The Spirit of the Laws, 1748)

Ludwig Wittgenstein:
"If a false thought is so much as expressed boldly and clearly, a great deal has already been gained." (Culture and Value, 1980 posthumous)

13. Expansion of knowledge

Al-Biruni:
"Once a sage asked why scholars always flock to the doors of the rich, whilst the rich are not inclined to call at the doors of scholars. 'The scholars' he answered , 'are well aware of the use of money, but the rich are ignorant of the nobility of science'." (Wikiquote)

Louis de Broglie:
"The actual state of our knowledge is always provisional and... there must be, beyond what is actually known, immense new regions to discover." (Forward to Causality and Chance in Modern Physics by David Bohm)

Louis de Broglie:
"No doubt theorist would much prefer to perfect and amend their theories rather than be obliged to scrap them continually. But this obligation is the condition and price of all scientific progress." (New Perspectives in Physics, 1962)

Louis de Broglie:
"The history of science shows that the progress of science has constantly been hampered by the tyrannical influence of certain conceptions that finally came to be considered as dogma. For this reason, it is proper to submit periodically to a very searching examination, principles that we have come to assume without any more discussion." (Will Quantum Physics Remain Indeterministic, 1953)

Amos Bronson Alcott:
"Yet the deepest truths are best read between the lines, and, for the most part, refuse to be written." (Concord Days, 1872)

Ralph Asher Alpher:
"There are two reasons you do science. One is the altruistic feeling that maybe you can contribute to mankind's store of knowledge about the world. The other and more personal thing is you want the approbation of your peers. Pure and simple." (Interview for Discover Magazine)

Torbern Bergman:
"A scientist strives to understand the work of Nature. But with our insufficient talents as scientists, we do not hit upon the truth all at once. We must content ourselves with tracking it down, enveloped in considerable darkness, which leads us to make new mistakes and errors. By diligent examination, we may at length little by little peel off the thickest layers, but we seldom get the core quite free, so that finally we have to be satisfied with a little incomplete knowledge." (Today in Science History)

Thomas Burnet:
"I can easily believe, that there are more invisible than visible beings in the universe." (Archaelogiae philosophicae: sive, doctrina antiqua de rerum originibus, libri duo)

Georg Cantor:
"Great innovation only happens when people aren't afraid to do things differently." (AZquotes.com)

Georg Cantor:
"A false conclusion once arrived at and widely accepted is not easily dislodged and the less it is understood the more tenaciously it is held." (AZquotes.com)

Carl von Clausewitz:
"Any complex activity, if it is to be carried on with any degree of virtuosity, calls for appropriate gifts of intellect and temperament. If they are outstanding and reveal themselves in exceptional achievements, their possessor is called a 'genius'." (1832, On War)

Marie Currie:
"I am among those who think that science has great beauty. A scientist in their laboratory is not only a technician: they are also a child placed before natural phenomena which impress them like a fairy tale." (Madame Curie: A Biography)

Marie Currie:
"...humanity also needs dreamers, for whom the disinterested development of an enterprise is so captivating that it becomes impossible for them to devote their care to their own material profit. Without doubt, these dreamers do not deserve wealth, because they do not desire it. Even so, a well-organized society should assure to such workers the efficient means of accomplishing their task, in a life freed from material care and freely consecrated to research." (Wikiquote)

Marie Currie:
"If I see anything vital around me, it is precisely that spirit of adventure, which seems indestructible and is akin to curiosity." (Quoted in Madame Curie: A Biography by Eve Curie Labouisse)

Giles Deleuze:
"Creation takes place in bottlenecks... it's by banging your head on the wall that you find a way through... You have to open up words, break things open, to free earth's vectors." (Goodreads.com)

Giles Deleuze:
"Every time someone puts an objection to me, I want to say, 'OK, OK, let's go on to something else'. Objections have never contributed anything." (AZquotes.com)

Giles Deleuze:
"To affirm is not to bear, carry, or harness oneself to that which exists, but on the contrary to unburden, unharness, and set free that which lives." (Nietzsche and Philosophy, 1962)

Jacques Derrida:

"I was wondering myself if I know where I am going. So I would answer you by saying, first, that I am trying precisely, to put myself at a point so that I do not know any longer where I am going." (Quoted in The Structuralist Controversy by Richard Macksey and Eugene Donato, 2007)

Jacques Derrida:

"So none of this looks like a blossoming or a completeness, but rather like impromptus, fits and starts that, precisely because of their incompleteness and non-coincidence... induced me to continue." (A Taste for the Secret, 1997)

Rene Descartes:
"So blind is the curiosity by which mortals are possessed, that they often conduct their minds along unexplored routes, having no reason to hope for success, but merely being willing to risk the experiment of finding whether the truth they seek lies there." (Rules for the Direction of the Mind, 1628)

John Dewey:
"Every great advance in science has issued from a new audacity of imagination." (The Quest for Certainty, 1929)

Edward Jan Dijksterhuis:
"The creation of modern science required a different philosophy. Man had to realize that if science is to grow, each generation must make its own contribution; and that the accumulated wisdom of antiquity is useful only as a starting point for new research." (Simon Stevin: Science in the Netherlands Around 1600, 1970)

Fyodor Dostoevsky:

"Oh, how hard it is to be the only one who knows the truth! But they won't understand that. No, they won't understand it." (The Dream of a Ridiculous Man, 1877)

Will Durant:
"Every science begins as philosophy and ends as art." (1926, The Story of Philosophy)

Albert Einstein:
"Nature shows us only the tail of the lion. But there is no doubt in my mind that the lion belongs with it even if he cannot reveal himself to the eye all at once because of his huge dimension." (Letter to Heinrich Zangger, 1914)

Albert Einstein:
"When I examine myself and my methods of thought I come to the conclusion that the gift of fantasy has meant more to me than my talent for absorbing positive knowledge." (Quoted in János : The Story of a Doctor by János Plesch)

Albert Einstein:
"I despaired of the possibility of discovering the true laws by means of constructive efforts based on known facts. The longer and the more despairingly I tried, the more I came to the conviction that only discovery of a universal formal principle could lead us to assured results." (Autobiographical Notes, 1949)

Albert Einstein:
"I am enough of an artist to draw freely upon my imagination. Imagination is more important than knowledge. For knowledge is limited, whereas imagination embraces the entire world, stimulating progress, giving birth to evolution." (Interview with the Saturday Evening Post, 1929)

Albert Einstein:
"As our circle of knowledge expands so does the circumference of darkness surrounding it." (Quoted in Paper Prototyping by Carolyn Snyder)

Enrico Fermi:
"Whatever Nature has in store for mankind, unpleasant as it may be, men must accept, for ignorance is never better than knowledge." (Goodreads.com)

Enrico Fermi:
"Actually there was no choice. Once basic knowledge is acquired, any attempt at preventing its fruition would be as futile as hoping to stop the earth from revolving around the sun." (Collected Papers of Enrico Fermi, 1939-1954)

Paul Feyerabend:
"The progress of science, of good science, depends on novel ideas and on intellectual freedom: science has very often been advanced by outsiders (remember that Bohr and Einstein regarded themselves as outsiders)." (How To Defend Society Against Science, 1975)

Paul Feyerabend:
"Combining this observation with the insight that science has no special method, we arrive a the result that the separation of science and non-science is not only artificial but also detrimental tot he advancement of knowledge. If we want to understand nature, if we want to master our physical surroundings, then we must use all ideas, all methods, and not just a small selection of them." (Against Method, 1975)

Paul Feyerabend:
"It is clear, then, that the idea of a fixed method, or of a fixed theory or rationality, rests on too naive a view of man and his surroundings... It is the principle: anything goes." (Against Method, 1975)

Johann Gottlieb Fichte:
"...How this knowledge can come into being, and what is in its inward and essential nature?" (Outline of the Doctrine of Knowledge, 1810)

Alexander Fleming
"It is the lone worker who makes the first advance in a subject: the details may be worked out by a team, but the prime idea is due to the enterprise, though and perception of an individual." (Wikiquote)

Alexander Fleming:
"When I woke up just after dawn on September 28, 1928, I certainly didn't plan to revolutionize all medicine by discovering the world's first antibiotic, or bacteria killer... But I guess that was exactly what I did." (AZQuotes.com)

Alexander Fleming:
"The unprepared mind cannot see the outstretched hand of opportunity." (AZQuotes.com)

Alexander Fleming:
"...never neglect an extraordinary appearance or happening. It may be - usually is, in fact - a false alarm that leads to nothing, but may on the other hand be the clue provided by fate to lead you to some important advance." (Quoted in Molecular Cloning by David Russell and Joseph Sambrook)

Alexander Fleming:
"For the birth of something new, there has to be a happening. Newton saw an apple fall; James Watt watched a kettle boil; Roentgen fogged some photographic plates. And these people knew enough to translate ordinary happenings into something new." (Quoted in The Life of Sir Alexander Fleming by Andre Maurois)

Sigmund Freud
"I am actually not at all a man of science, not an observer, not an experimenter, not a thinker. I am by temperament nothing but a conquistador - an adventurer, if you want it translated with - all the curiosity, daring and tenacity characteristic of a man of this sort." (Letter to Wilhelm Fliess, 1900)

Ragnar Frisch:
"Deep in the human nature there is an almost irresistible tendency to concentrate physical and mental energy on attempts at solving problems that seem to be unsolvable." (From Utopian Theory to Practical Applications, 1970)

Evariste Galois:
"[This] science is the work of the human mind, which is destined rather than to know, to seek the truth rather than to find it." (Quoted in Mathematics by Morris Kline)

George Gamow:
"It is well known that theoretical physicists cannot handle experimental equipment; it breaks whenever they touch it. [Wolfgang] Pauli was such a good theoretical physicist that something usually broke in the lab whenever he merely stepped across the threshold." (1966, Thirty Years that Shook Physics: The Story of Quantum Theory)

Carl Friedrich Gauss:
"The enchanting charms of this sublime science reveal themselves in all their beauty only to those who have the courage to go deeply into it." (Letter to Sophie Germain, 1807)

Carl Friedrich Gauss:
"If others would but reflect on mathematical truths as deeply and as continuously as I have, they would make my discoveries." (Quoted in the World of Mathematics by J. R. Newman)

Stephen Jay Gould:
"Revolutionary thinkers are not, primarily, gathers of facts, but weavers of new intellectual structures." (Bully for Brontosaurus, 1991)

Stephen Hawking:
"I don't believe that the ultimate theory will come by steady work along existing lines. We need something new. We can't predict what that will be or when we will find it because if we knew that we would have found it already!" (Science Watch, 1994)

Georg W. F. Hegel:
"The force of mind is only as great as its expression; its depth only as deep as its power to expand and lose itself." (The Phenomenology of Spirit, 1807)

Otto Hahn:
"Usually, a discovery is not made in the easiest but on a complicated way; the simple cases show up only later." (1962, Vom Radiothor zur Uranspaltung. Eine wissenschaftliche Selbstbiographie)

Martin Heidegger:
"Making itself intelligible is suicide for philosophy. Those who idolize 'facts' never notice that their idols only shine in a borrowed light." (Quoted in Contributions to Philosophy by Parvis Emad)

Martin Heidegger:
"In everything well known something worthy of thought still lurks." (Nietzsche, 1961)

John Herschel:
"To ascend to the origin of things and speculate on the creation, is not the business of the natural philosopher. An humbler field is sufficient for him in the endeavor to discover, as far as our faculties will permit; what are these primary qualities impressed on matter, and to discover the spirit of the laws of nature." (1831, A Preliminary Discourse on the Study of Natural Philosophy)

David Hilbert:
"One can measure the importance of a scientific work by the number of earlier publications rendered superflous by it." (Quoted in Mathematical Circles Revisited by Howard Whitley Eves)

Alexander von Humboldt:
"There are three stages of scientific discovery: first people deny it is true; then they deny it is important; finally they credit the wrong person." (Good Reads)

Francis Hutcheson:
"Whoever voluntarily undertakes the necessary office of rearing and educating, obtains the parental power without generation." (1755, A System Of Moral Philosophy)

Walter Isaacson:

"As [Leonardo da Vinci] did with many of his paintings, he would hang on to the treatises that he was drafting, occasionally make a few new strokes and refinements, but never see them through to being released to the public as complete." (Leonardo da Vinci, 2017)

Edward Jenner:
"While the vaccine discovery was progressive, the joy I felt at the prospect before me of being the instrument destined to take away from the world one of its greatest calamities [smallpox], blended with the fond hope of enjoying independence and domestic peace and happiness, was often so excessive that, in pursuing my favourite subject among the meadows, I have sometimes found myself in a kind of reverie." (Quoted in The Life of Dr. Jenner, 1827)

Carl Jung:
"All ordinary expression may be explained causally, but creative expression which is the absolute contrary of ordinary expression, will be forever hidden from human knowledge." (Psychology and poetry, 1930)

Franz Kafka:
"I think we ought to read only the kind of books that wound and stab us. If the book we are reading doesn't wake us up with a blow on the head, what are we reading it for? ... we need the books that affect us like a disaster, that grieve us deeply, like the death of someone we loved more than ourselves, like being banished into forests far from everyone, like a suicide. A book must be the axe for the frozen sea inside us." (Letter to Oskar Pollak, January 1904)

Ibn Khaldun:
"The sciences of only one nation, the Greeks, have come down to us, because they were translated through Al-Ma'mun's efforts. He was successful in this direction because he had many translators at his disposal and spent much money in this connection." (Muqaddimah, 1377)

Thomas Kuhn:
"Scientific revolutions are inaugurated by a growing sense... that an existing paradigm has ceased to function adequately in the exploration of an aspect of nature to which that paradigm itself had previously led the way." (The Structure of Scientific Revolutions, 1962)

Thomas Kuhn:
"Normal science, the puzzle-solving activity... is a highly cumulative enterprise, eminently successful in its aim, the steady extension of the scope and precision of scientific knowledge." (The Structure of Scientific Revolutions, 1962)

Joseph-Louis Lagrange:
"Newton was the greatest genius that ever existed, and the most fortunate, for we cannot find more than once a system of the world to establish." (Introduction to Astronomy by F. R. Moulton)

Joseph-Louis Lagrange:
"It took them only an instant to cut off that head, but France may not produce another like it in a century." (Quoted in Annual Editions: Western Civilization by William Hughes regarding the beheading of Antoine Lavoisier)

Pierre-Simon Laplace:
"Man follows only phantoms." (Last words according to Morgan's Budget of Paradoxes)

Bruno Latour
"If one looks at the works of Newton to Einstein, they were never scientists in the way modernity understands the term." (Brainy Quote)

Antonie van Leeuwenhoek:
"How inscrutable and incomprehensible are the hidden works of Nature!" (Brainyquote.com)

Monsignor Georges Lemaitre

"Scientific progress is the discovery of a more and more comprehensive simplicity... The previous successes give us confidence in the future of science: we become more and more conscious of the fact that the universe is cognizable." (Today in Science History)

George Henry Lewes:
"Philosophy and art both render the invisible visible by imagination." (The Principles of Success in Literature, 1865)

George Henry Lewes:
"Where sense observes two isolated objects, imagination discloses two related objects. We had not see it before; it is apparent now." (The Principles of Success in Literature, 1865)

John Locke:
"The improvement of the understanding is for two ends: first, for our own increase of knowledge; secondly, to enable us to deliver and make out that knowledge to others." (Some Thoughts Concerning Reading and Study)

Thomas Robert Malthus:
"The finest minds seem to be formed rather by efforts at original thinking, by endeavors to form new combinations, and to discover new truths, than by passively receiving the impressions of other men's ideas." (An Essay on the Principle of Population, 1798 revised 1826)


James Clerk Maxwell:
"It is of great advantage to the student of any subject to read the original memoirs on that subject, for science is always most completely assimilated when it is in the nascent state..." (A Treatise on Electricity and Magnetism, 1873)

John Stuart Mill

"Persons of genius, it is true, are, and always like to be, a small minority; but in order to have them, it is necessary to preserve the soil in which they grow. Genius can only breathe freely in an atmosphere of freedom." (On Liberty, 1859)m

Augustus De Morgan:
"The way to enlarge the settled country has not been by keeping within it, but by making voyages of discovery, and I am perfectly convinced that the student should be exercised in this manner; that is, that they should be taught how to examine the boundary, as well as how to cultivate the interior." (The Differential and Integral Calculus, 1836)

Augustus De Morgan:
"All the men who are now called discoverers, in every matter ruled by thought, have been men versed in the minds of their predecessors and learned in what had been before them. There is not one exception." (A Budget of Paradoxes, 1872)

Augustus De Morgan:
"The thirteen books of Euclid must have been a tremendous advance, probably even greater than that contained in the Principia of Newton." (Quoted in Dictionary of Greek and Roman Biology and Mythology by William Smith)

Wolfgang Amadeus Mozart:
"I am never happier than when I have something to compose, for that, after all, is my sole delight and passion." (AZQuotes.com)

Wolfgang Amadeus Mozart:
"I pay no attention whatever to anybody's praise or blame. I simply follow my own feelings." (Goodreads.com)

Wolfgang Amadeus Mozart:

"I really do not aim at any originality." (AZQuotes.com)

Isaac Newton

"I do not know what I may appear to the world, but to myself I seem to have been only like a boy playing on the sea-shore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me." (Quoted in Memoirs of the Life, Writings and Discoveries of Sir Isaac Newton)

Friedrich Nietzsche:
"The value of many men and books rests solely on their faculty for compelling all to speak out the most hidden and intimate things." (Quoted in Bartlett's Familiar Quotations)

Alice Oswald:
"Poems, like dreams, have a visible subject and an invisible one. The invisible one is the one you can't choose, the one that writes itself. Not a message that comes at the end of the poem, more like a pathological condition that deforms every word." (Quoted in Modern Women Poets by Deryn Rees-Jones)

Linus Pauling:
"The scientists of the past whom we now recognize as great are those who were gifted with transcendental imaginative powers..." (Imagination in Science, 1943)

Linus Pauling:
"If you want to have good ideas you must have many ideas. Most of them will be wrong and what you have to learn is which ones to throw away." (Quoted in The Impact of Linus Pauling on Molecular Biology by Francis Crick)

Charles Sanders Peirce:
"Wherever ideas come together they tend to weld into general ideas; and whenever they are generally connected, general ideas govern the connection; and these general ideas are living feelings spread out." (The Law of Mind, 1892)

Pablo Picasso:
"I can hardly understand the importance given to the word 'research' in connection with modern painting. In my opinion to search means nothing in painting. To find is the thing. Nobody is interested in following a man who, with his eyes fixed on the ground, spends his life looking for the purse that fortune should put in his path. The one who finds something no matter what it might be, even if his intention were not to search for it, at least arouses our curiosity, if not our admiration." (1923, Picasso Speaks)

Max Planck
"New scientific ideas never spring from a communal body, however organized, but rather from the head of an individually inspired researcher who struggles with his problems in lonely thought and united all his thought on one single point which is his whole world for the moment." (Address on the 25th anniversary of the Kaiser-Wilhelm Gesellschaft, 1936)

Wilhelm Rontgen:
"Having discovered the existence of a new kind of rays, I of course began to investigate what they would do... It soon appeared from the tests that the rays had penetrative power to a degree hitherto unknown. They penetrated paper, wood, and cloth with ease; and the thickness of the substance made no perceptible difference, within reasonable limits." (The New Marvel in Photography, 1896)

Wilhelm Rontgen:
"In a few minutes there was no doubt about it. Rays were coming from the tube which had a luminescent effect upon the paper... It seemed a first a new kind of invisible light. It was clearly something new, something unrecorded." (The New Marvel in Photography, 1896)

Jean-Jacques Rousseau:
"Those whom nature intended for her disciples have not needed masters. Bacon, Descartes and Newton, those teachers of mankind had themselves no teachers. What guide indeed could have taken them so far as their sublime genius directed them? Ordinary masters would only have cramped their intelligence by confining it within the narrow limits of their own capacity." (Discourse on the Sciences and Arts, 1750)

Bertrand Russell:
"Every great study is not an end in itself, but also a means of creating and sustaining a lofty habit of mind." (Mysticism and Logic and Other Essays, 1918)

Bertrand Russell:
"In astronomy, the law of gravitation is plainly better worth knowing than the position of a particular planet on a particular night, or even on every night throughout the year. There are in the law a splendour and simplicity and sense of mastery which illuminate a mass of otherwise uninteresting details..." (On History, 1904)

Frederick Sanger:
"It is like a voyage of discovery into unknown lands, seeking not for new territory but for new knowledge. It should appeal to those with a good sense of adventure." (Brainy Quote)

Bertrand Russell:
"The scientific attitude of mind involves a sweeping away of all other desires in the interests of the desire to know—it involves suppression of hopes and fears, loves and hates, and the whole subjective emotional life, until we become subdued to the material, able to see it frankly, without preconceptions, without bias, without any wish except to see it as it is, and without any belief that what it is must be determined by some relation, positive or negative, to what we should like it to be, or to what we can easily imagine it to be." (1918, Mysticism and Logic and Other Essays)


George Sarton:
"In a sense, this is still true today; the real pioneers are so far ahead of the crowd (even a very literate crowd) that they remain almost alone..." (A History of Science, Volume 2, 1959 posthumous)

George Sarton:
"It is childish to assume that science began in Greece; the Greek 'miracle' was prepared by millennia of work in Egypt, Mesopotamia and possibly other regions... Greek science was less an invention than a revival." (A History of Science, Volume 1, 1952)

George Sarton:
"...[the history of science] should be used only for its own purpose, to illustrate impartially the working of reason against unreason, the gradual unfolding of truth in all its forms..." (AZquotes.com)

Friedrich Schelling:
"Just as a sculptor does not cease to be a work of art even if it lies at the bottom of the sea, so indeed every work of philosophy endures, even if uncomprehended in its own time." (Philosophy and Religion, 1804)

Arthur Schopenhauer

"Talent hits a target no one else can hit; Genius hits a target no one else can see." (1819, The World as Will and Representation)

Glenn Seaborg:
"There is a beauty in discovery. There is mathematics in music, a kinship of science and poetry in the description of nature, and exquisite form in a molecule. Attempts to place different disciplines in different camps are revealed as artificial in the face of the unity of knowledge. All literate men are sustained by the philosopher, the historian, the political analyst, the economist, the scientist, the poet, the artisan and the musician." (1958, Statement upon being appointed as UC Berkeley chancellor)

Adam Sedgwick:
"As a system of philosophy it is not like the Tower of Babel, so daring its high aim as to seek a shelter against God's anger; but it is like a pyramid poised on its apex." (Brainy Quote)

Nikola Tesla:
"The scientific man does not aim at an immediate result. He does not expect that his advanced ideas will be readily taken up. His work is like that of the planter - for the future. His duty is to lay the foundation for those who are to come, and point the way. He lives and labors and hopes." (Radio Power will Revolutionize the Way, 1934)

Nikola Tesla:
"I do not think there is any thrill that can go through the human heart like that felt by the inventor as he sees some creation of the brain unfolding to success... Such emotions make a man forget food, sleep, friends, love, everything." (Quoted in Marconi and Tesla: Pioneers of Radio Communication)

Leonardo da Vinci:
"Fire destroys falsehoods, that is sophistry and restores truth, driving out darkness." (The Notebooks of Leonardo da Vinci, translated by Edward MacCurdy)

Robert Watson-Watt:
"There is a great deal of emotional satisfaction in the elegant demonstration, in the elegant ordering of facts into theories, and in the still more satisfactory, still more emotionally exciting discovery that the theory is not quite right and has to be worked over again, very much as any other work of art—a painting, a sculpture has to be worked over in the interests of aesthetic perfection. So there is no scientist who is not to some extent worthy of being described as artist or poet." (1948, Scientist and Citizen)

James Watt:
"I had gone on a walk on a fine Sabbath afternoon... I was thinking upon the engine at the time, and had gone as far as the herd's house, when the idea came into my mind that as steam was an elastic body it would rush into a vacuum, and if a communication were made between the cylinder and an exhausted vessel it would rush into it, and might be there condensed without cooling the cylinder." (Quoted in Reminiscences of James Watt by Robert Hart)

James Watt:
"When once the idea of the separate condensation was started, all these improvements followed as corollaries in quick succession, so that in the course of one or two days the invention was thus far complete in my mind, and I immediately set about an experiment to verify it practically." (Notes on Professor Robison's Dissertation on Steam-engines, 1769)

John Archibald Wheeler:
"We live on an island surrounded by a sea of ignorance. As our island of knowledge grows, so does the shore of our ignorance." (1922, from Scientific American)

Simone Weil:
"Art is the symbol of the two noblest human efforts: to construct and to refrain from destruction." (Prewar Notebook)

Simone Weil:
"To anyone who does actually consent to directing his attention and love beyond the world, towards the reality that exists outside the reach of all human faculties, it is given to succeed in doing so." (Draft for a Statement of Human Obligation, posthumous)

William Whewell:
"The system becomes more coherent as it is further extended. The elements which we require for explaining a new class of facts are already contained in our system." (Philosophy of the Inductive Sciences, 1840)

William Whewell:
"A very important advantage would be gained if any light could be thrown upon the modes of discovering truth, the powers that we possess for this end, and the points to which there may most profitably be applied." (History of the Inductive Sciences, 1837)

William Whewell:
"The great reform of philosophy and method in which Bacon so eloquently called upon men to unite their exertions in his day has, even in ours, been very imperfectly carried into effect. And even if his plan had been fully executed, it would now require to be pursed and extended." (History of the Inductive Sciences, 1837)

William Whewell:
"[Scientific discoveries] have been preceded by a period which we may call their prelude, during which the ideas and facts on which they turned were called into action; were gradually evolved into clearness and connexion, permanency and certainty." (History of the Inductive Sciences, 1837)

Alfred North Whitehead:
"Every intellectual revolution which has ever stirred humanity into greatness has been a passionate protest against inert ideas." (The Aims of Education, 1929)

Bernard Williams:
"As Roland Barthes said, those who do not re-read condemn themselves to reading the same story everywhere: 'they recognize what they already think and know." (Truth and Truthfulness, 2002)

Wilbur Wright
"For some years I have been afflicted with the belief that flight is possible to man. My disease has increased in severity and I feel that it will soon cost me an increased amount of money if not my life. I have been trying to arrange my affairs in such a way that I can devote my entire time for a few months to experiment in this field." (Letter to Octave Chanute, 1900)

14. Experiments

Aristotle:
"We may assume the superiority ceteris paribus [all things being equal] of the demonstration which derives from fewer postulates or hypotheses..." (Posterior Analytics)

Isaac Asimov:
"Science doesn't purvey absolute truth. Science is a mechanism. It's a way of trying to improve your knowledge of nature. It's a system for testing your thoughts against the universe and seeing whether they match. And this works, not just for the ordinary aspects of science, but for all of life." (Interview on Bill Moyers, 1988)

A. J. Ayer:
"The criterion which we use to test the genuineness of apparent statements of fact is the criterion of verifiability. We say that a sentence is factually significant to any given person, if, and only if, he knows how to verify the proposition which it purports to express - that is, if he knows what observations, would lead him, under certain conditions, to accept the proposition as being true, or reject it as being false." (Language, Truth and Logic, 1936)

Roger Bacon:
"Experimental science is the queen of sciences, and the goal of all speculation." (Quoted in Science at the Medieval Universities by James Walsch)

Roger Bacon:
"The strongest argument proves nothing so long as the conclusions are not verified by experience. Experimental science is the queen of sciences, and the goal of all speculation." (Quoted in Science at the Medieval Universities by James J. Walsch)

Roger Bacon:
"Argument is conclusive... but... it does not remove doubt, so that the mind may never rest in the sure knowledge of the truth, unless it finds it by the method of experiment. For if any man who never saw fire proved by satisfactory arguments that fire burns, his hearer's mind would never be satisfied, nor would he avoid the fire until he put his hand in it that he might learn by experiment what argument taught." (Quoted in Memorable Quotations by Carol A. Dingle)


Claude Bernard:
"What really should be done, instead of gathering facts empirically, is to study them more accurately, each in its special determinism." (1865, Introduction à l'Étude de la Médecine Expérimentale)

Claude Bernard:
"We must never make experiments to confirm our ideas, but simply to control them." (Bulletin of New York Academy of Medicine, 1928)

Claude Bernard:
"Indeed, proof that a given condition always precedes or accompanies a phenomenon does not warrant concluding with certainty that a given condition is the immediate cause of that phenomenon. It must still be still established that when this condition is removed the phenomenon will no longer appear." (Introduction a l'Etude de la Medecine Experimental, 1865)

Alfred Binet:
"Mere numbers cannot bring out... the intimate essence of experiment. This conviction comes naturally when one watches a subject at work... What things can happen!" (La Suggestibilite, 1990)

Alfred Binet:
"I wish that one would be persuaded that psychological experiments, especially those on the complex functions, are not improved [by large studies]; the statistical method gives only mediocre results." (Today in Science History)

Joseph Black:
"A nice adaptation of conditions will make almost any hypothesis agree with the phenomena. This will please the imagination but does not advance our knowledge." (AZ Quotes)

Niels Bohr:
"...simply by the word 'experiment' we refer to a situation where we can tell others what we have done and what we have learned..." (Quoted in Discussions withe Einstein on Epistemological Problems in Atomic Physics by Albert Schilpp)

Niels Bohr:
"Physics is to be regarded not so much the study of something a priori given, but rather as the development of methods ordering and surveying human experience." (The Unity of Human Knowledge, 1960)

Lord Bolingbroke:
"Philosophers hasten too much from the analytic to the synthetic method; that is, they draw general conclusions from too small a number of partial observations and experiments." (Quoted in Prose Quotations from Socrates to Macaulay by Austin Allibone, 1903)

Max Born:
"I believe there is no philosophical high-road in science, with epistemological signposts. No, we are in a jungle and find our way by trial and error, building our road behind us as we proceed." (Experiment and Theory in Physics)

Denis Diderot

"In order to shake a hypothesis, it is sometimes not necessary to do anything more than push it as far as it will go." (On the Interpretation of Nature, 1753)

Erle Elsworth:
"Inductive reasoning is reasoning from particular facts to a general law, or proposition, called the conclusion. Inductive reasoning is synthetic; that is, it builds up the law (the proposition) by giving particular instances in which that law is true. It is by inductive reasoning that we have established most of our laws in the natural sciences." (Illustrated Lessons in Composition and Rhetoric, 1912)

Richard Feynman:
"In general, we look for a new law by the following process: first we guess it... Then we compute the consequences of the guess to see what, if it is right, if this law that we guessed is right, to see what it would imply. And then we compare it directly with observation to see if it works. If it disagrees with the experiment, then it's wrong." (QED; The Strange Theory of Light and Matter, 1985)

Richard Feynman:
"...if you're doing an experiment, you should report everything that you think might make it invalid. Not only what you think is right about it; other causes that could possibly explain you results; and things you thought of that you've eliminated by some other experiment, and how they worked - to make sure the other fellow can tell they have been eliminated." (Adapted from 1974 Cal Tech Commencement)

Richard Feynman:
"In summary, the idea is to try to give all  of the information to help others to judge the value of your contribution; not just the information that leads to judgement in one particular direction or another." (Adapted from 1974 Cal Tech Commencement)

Ronald Fisher:
"The analysis of variance is not a mathematical theorem, but rather a convenient method of arranging the arithmetic." (Quoted in Statistics in agricultural research by J. Wishart)

Ronald Fisher:
"However, perhaps the main point is that you are under no obligation to analyse variance into its parts if it does not come apart easily, and its unwillingness to do so naturally indicates that one’s line of approach is not very fruitful." (Letter to L. Hogben, 1933)

Ronald Fisher:
"The value for which P=0.05, or 1 in 20, is 1.96 or nearly 2; it is convenient to take this point as a limit in judging whether a deviation ought to be considered significant or not. Deviations exceeding twice the standard deviation are thus formally regarded as significant. Using this criterion we should be led to follow up a false indication only once in 22 trials, even if the statistics were the only guide available. Small effects will still escape notice if the data are insufficiently numerous to bring them out, but no lowering of the standard of significance would meet this difficulty.” (The Design of Experiments, 1935)

Ronald Fisher:
"Critical tests of this kind may be called tests of significance, and when such tests are available we may discover whether a second sample is or is not significantly different from the first." (Statistical Methods for Research Workers, 1925)

Ronald Fisher:
"In relation to any experiment we may speak of this hypothesis as the 'null hypothesis', and it should be noted that the null hypothesis is never proved or established, but is possibly disproved, in the course of experimentation. Every experiment may be said to exist only in order to give the facts a chance of disproving the null hypothesis." (The Design of Experiments, 1935)

Erving Goffman:
"So I ask that these papers be taken for what they merely are: exercises, trials, tryouts, a means of displaying possibilities, not establishing fact." (Wikiquote)

Ian Hacking:
"I hope [to] initiate a Back-to-Bacon movement, in which we attend more seriously to experimental science. Experimentation has a life of its own." (AZquotes.com)

David Hume:
"We must therefore glean up our experiments in this science from a cautious observation of human life, and take them as they appear in the common course of the world, by men's behavior in company, in affairs and in pleasures. Where experiments in this kind are judiciously collect and compares we may hope to establish on them a science, which will not be inferior in uncertainty, and will be much superior in utility to any other of human comprehension." (A Treatise  of Human Nature, 1739)

David Hume:
"The experimental reasoning itself, which we possess in common with beasts, and on which the whole conduct of life depends, is nothing but a species of instinct or mechanical power, that acts in us unknown to ourselves." (An Enquiry Concerning Human Understanding, 1748)

William Stanley Jevons:
"In reality, there is no such thing as an exact science." (The Theory of Political Economy, 1871)

Immanuel Kant:
"Thus only has the study of nature entered on the secure method of a science, after having for many centuries done nothing but grope in the dark." (Critique of Pure Reason, 1781)

Pierre-Simon Laplace:
"Analysis and natural philosophy owe their most important discoveries to this fruitful means, which is called induction. Newton was indebted to it for his theorem of binomial and the principle of universal gravity." (A Philosophical Essay on Probabilities, 1902)

Antoine Lavoisier:
"We must trust to nothing but facts: These are presented to us by Nature, and cannot deceive. We ought, in every instance, to submit our reasoning to the test of experiment, and never to search for truth but by the natural road of experiment and observation." (Elements of Chemisty, 1790)

Thomas Robert Malthus:
"It is an acknowledged truth in philosophy that a just theory will always be confirmed by experiment." (An Essay on the Principle of Population, 1798)

James Clerk Maxwell:
"The aim of an experiment of illustration is to throw light upon some scientific idea so that the student may be able to grasp it... The phenomenon which we wish to observe or to exhibit is brought into prominence, instead of being obscured and entangled among other phenomena, as it would when it occurs in the ordinary course of nature." (The Scientific Papers of James Clerk Maxwell, posthumous)

John Stuart Mill:
"Induction may be defined the operation of discovering and proving general propositions." (A system of Logic, Ratiocinative and Inductive, 1858)

Isaac Newton:
"The best and safest method of philosophizing seems to be, first to enquire diligently into the properties of things, and to establish these properties by experiment, and then to proceed more slowly to hypothesis for the explanation of them. For hypotheses should be employed only in explaining the properties of things, but not assumed in determining them, unless so far as they may furnish experiments." (Letter to Ignatius Pardies, 1672)

Friedrich Nietzsche:
"To what extent can truth endure incorporation? That is the question; that is the experiment." (The Gay Science, 1882)

Hans Christian Orsted:
"The agreement of this law with nature will be better seen by the repetition of experiments than by a long explanation." (1820, Experiments on the Effect of a Current of Electricity on the Magnetic Needle, Annals of Philosophy)

Henri Poincare:
"Induction applied to the physical sciences is always uncertain because it rests on a  belief in a general order of the universe..." (Science and Hypothesis, 1901)

Karl Popper:
"Bold ideas, unjustified anticipations, and speculative thought, are our only means for interpreting nature: our only organon, our only instrument, for grasping her. And we must hazard them to win our prize. Those among us who are unwilling to expose their ideas to the hazard of refutation do not take part in the scientific game." (1934, The Logic of Scientific Discovery)

Karl Popper:
"Science is one of the very few human activities - perhaps the only one - in which errors are systematically criticized and fairly often, in time, corrected." (Conjectures and Refutations, 1963)

Willard van Orman Quine:
"The scientist is indistinguishable from the common man in his sense of evidence, except that the scientist is more careful." (AZquotes.com)

Willard van Orman Quine:
"My position is a naturalistic one; I see philosophy not as a priori propaedeutic or groundwork for science, but as continuous with science." (AZquotes.com)

Jane Roberts:
"Fact is that science itself must change, as it discovers that its net of evidence is equipped only to catch certain kinds of fish, and that it is constructed of webs of assumptions that can only hold certain varieties of reality, while others escape its net entirely." (The God of Jane: A Psychic Manifesto)

Wilhelm Rontgen:
"I am not a prophet, and I am opposed to prophesying. I am pursuing my investigations, and as fast as my results are verified I shall make them public." (1838, The New Marvel in Photography)

Bertrand Russell:
"It has only been very slowly that scientific method, which seeks to reach principles inductively from observation of particular facts, has replaced the Hellenic belief in deduction  from luminous axioms derived from the mind of the philosopher." (A History of Western Philosophy, 1945)

Noah Smith:
"Each science has its own 'scientific method', and this method evolves in time. We just have to figure out what seems to be working and what doesn't seem to be working, and adjust accordingly." (Judgement calls and the philosophy of science, 2012)

Patrick Suppes:
"Only the results of the experiment are reported in any serious detail. The procedures are not." (Pragmatism in Physics, 1998)

William Thomson:
"In all cases when a particular agent or cause is to be studied, experiments should be arranged in such a way as to lead if possible to results depending on it alone..." (Treatise on Natural Philosophy with Peter Guthrie Tait, 1867)

Leonardo da Vinci
"Though I may not, like them, be able to quote other authors, I shall rely on that which is much greater and more worthy - on experience, the mistress of their Masters. They go about puffed up and pompous, dressed and decorated with [the fruits], not of their own labors, but of those of others. And they will not allow me my own. They will scorn me as an inventor." (Quoted by The Notebooks of Leonardo da Vinci by Rudolf Flesch)

Andreas Vesalius:
"I am not accustomed to saying anything with certainty after only one or two observations." (De Humani Corporis Fabrica Libri Septem, 1543)

Alessandro Volta:
"The language of experiment is more authoritative than any reasoning: facts can destroy our ratiocination - not vice versa." (Today in Science History)

William Whewell:
"We have no lack of proof that mere activity of thought is... inefficient in producing real knowledge... How impossible the formation of these sciences is without a constant and careful reference to observation and experiment." (History of the Inductive Sciences, 1837)

E. O. Wilson:
"My definition of a scientist is that you can complete the following sentence: 'He or she has shown that...'" (Quoted in Why Richard Dawkins is 'not a scientist' by Steve Connor)

15. Free will

Thomas Aquinas:
"The greatness of the human being consists in this: that it is capable of the universe." (De Veritate)

Thomas Aquinas:
"Reason in man is rather like God in the world." (Opuscule II, De Regno)

Simone de Beauvoir:
"I wish that every human life might be pure transparent freedom." (The Blood of Others, 1946)

Henri Bergson:
"The role of the body was thus to reproduce in action the life of the mind, to emphasize its motor articulations as the orchestra conductor does for a musical score; the brain did not have thinking as its function but that of hindering the thought from becoming lost in dream; it was the organ of attention to life." (The Creative Mind: An Introduction to Metaphysics, 1934)

Henri Bergson:
"Men do not sufficiently realise that their future is in their own hands... the essential function of the universe, which is a machine for the making of gods." (The Two Sources of Morality and Religion, 1932)

Jacob Bronoswki:
"What we really mean by free will... is the visualizing of alternatives and making a choice between them." (The Origins of Knowledge and Imagination, 1978)

Giles Deleuze:
"What counts is the question, of what is a body capable? And thereby he sets out on of the most fundamental questions in his whole philosophy..." (Expressionism in Philosophy: Spinoza, 1990)

John Dewey:
"Individuality is the source of whatever is unpredictable in the world." (Time and Individuality, 1940)

Freeman Dyson:
"The philosophical problem of chance and free will are closely related." (Infinite in All Directions, 1988)

Amit Goswami:
"In this view, consciousness imposes 'downward causation'. In other words, our free will is real." (Scientific Proof of the Existence of God, 1997)

Stephen Jay Gould:

"Organisms are not billiard balls, propelled by simple and measurable external forces to predictable new positions on life's pool table." (119850, The Panda's Thumb)

John Maynard Keynes:
"Ideas shape the course of history." (The Peter Plan: A Proposal for Survival by Lawrence Peter, 1976)

Soren Kierkegaard:
"Above all do not forget your duty to love yourself; do not permit the fact that you have been set apart from life in a way, been prevented from participating actively in it, and that you are superflous in the obtruse eyes of a busy world, above all, do not permit this to deprive you of your idea of yourself..." (Letter to Kierkegaard's cousin Hans Peter, 1848)

Soren Kierkegaard:
"As soon as the actuality of freedom and of spirit is posited, anxiety is canceled." (Concept of Anxiety, 1844)

Jules Michelet:
"You are one of the forces of nature." (Brainy Quotes)

Michel de Montaigne:
"Not being able to govern events, I govern myself." (Essais, 1580)

Michel de Montaigne:
"The greatest thing in the world is to know how to belong to oneself." (Essais, 1580)

G. E. Moore:
"Moral conduct, or duty, is defined as the obligation to select that action which will achieve more good than any alternative action..." (Goodreads.com)

Charles Sanders Peirce:
"The truth is, the mind is not subject to 'law' in the same rigid sense that matter is." (The Law of Mind, 1892)

Jean-Jacques Rousseau:
"That man is truly free who desires what he is able to perform, and does what he desires. This is my fundamental maxim. Apply it to childhood, and all the rules of education spring from it." (Emile, or On Education, 1762)

Jean-Paul Sartre:
"Imagination is not an empirical or superadded power of consciousness, it is the whole of consciousness as it realizes its freedom." (1936, Imagination: A Psychological Critique)

Arthur Schopenhauer:
"Man can do what he wills but he cannot will what he wills," (On the Freedom of the Will, 1839)

Arthur Schopenhauer:
"My body and my will are one." (The World and Will as Representation, 1819)

Arthur Schopenhauer:
"Spinoza says that if a stone which has been projected through the air, had consciousness, it would believe that it was moving of its own free will. I add this only, that the stone would be right. The impulse given it is for the stone what the motive is for me, and what in the case of the stone appears as cohesion, gravitation, rigidity, is in its inner nature the same as that which I recognize in myself as will, and what the stone also, if knowledge were given to it, would recognize as will." (The World and Will as Representation, 1819)

Henry David Thoreau:
"If a man believes and expects great things of himself, it makes no odds where you put him, or what you show him... he will be surrounded by grandeur. He is in the condition of a healthy and hungry man..." (Letter to Harrison Blake, 1860)

Henry David Thoreau:
"If a man does not keep pace with his companions, perhaps it is because he hears a different drummer." (Walden, 1854)

Henry David Thoreau:
"If one advances confidently in the direction of his dreams, and endeavors to live the life which he has imagined, he will meet with a success unexpected in common hours." (Walden, 1854)

Henry David Thoreau:
"Life consists with wildness. The most alive is the wildest. Not yet subdued to man, its presence refreshes him." (Walking, 1862)

Max Weber:
"This striving becomes understood completely as an end in itself - to such an extent that it appears as fully outside the normal course of affairs and simply irrational, at least when viewed from the perspective of the 'happiness' or 'utility' of the single individual. Here, people are oriented to acquisition as the purpose of life; acquisition is no longer viewed as a means to the end of satisfying the substantive needs of life." (The Protestant Ethic and the Spirit of Capitalism, 1905)

16. Grammar

J. L. Austin:
"It may justly be urged that properly speaking, what alone has meaning, is the sentence." (Philosophical Papers, 1979 posthumous)

Rudolf Carnap:
"By the logical syntax of language, we mean the formal theory of the linguistic forms of that language - the systematic statement of the formal rules which govern it together with the development of the consequences which follow from these rules." (Logical Syntax of Language, 1934)

William Cobbet:
"Grammar, perfectly understood enables us, not only to express our meaning fully and clearly, but so to express it as to enable us to defy the ingenuity of man to give to our words any other meaning than that which we ourselves intend them to express." (A Grammar of the English Language, 1818)

Stanley Fish:
"Before the words slide into their slot, they are just discrete items, pointing everywhere and nowhere." (How to Write a Sentence and How to Read One, 2011)

Geoffrey Leech:
"The grammar seen as the system of rules and options underlying usage, has been very stable for the past few centuries. What might have changed though are stylistic conventions or expectations of formality." (Change in contemporary English, 2009)

Talcott Parsons:
"The most elementary communication is not possible without some degree of conformity to the 'conventions' of the symbolic system." (The Social System, 1951)

Hilary Putnam:
"It was Rudolf Carnap's dream for the last three decades of his life to show that science proceeds by a formal syntactic method; today no one to my knowledge holds out any hope for that project." (Quoted in Pragmatism and Realism by Conant and Zeglen)

Mark Twain:
"To be serious, I write good grammar myself, but not in that spirit, I am thankful to say. That is to say, my grammar is of a high order, though not at the top. Nobody's is. Perfect grammar (persistent, continuous, sustained) is the fourth dimension, so to speak many have sought it, but none has found it." (Quoted in Autobiography of Mark Twain by University California Press)

Richard Whatley:
"No one complains of the rules of grammar as fettering language; because it is understood that correct use is not founded on grammar, but grammar on correct use. A just system of logic of rhetoric is analogous, in this respect, to grammar..." (Elements of rhetoric, 1828)

Ludwig Wittgenstein:
"For remember that in general we don't use language according to strict rules; it hasn't been taught to us by means of strict rules, either." (The Blue Book, 1965 posthumous)

Ludwig Wittgenstein:
"People are deeply imbedded in philosophical, i.e. grammatical confusions. And to free them presupposes pulling them out of the immensely manifold connections they are caught up in."(Philosophical Occasions, 1993 posthumous)

17. History

Peter Berger:
"The symbolic universe also orders history. It locates all collective events in a cohesive unity that includes past, present and future." (The Social Cohesion of Reality, 1966)

Thomas Carlyle:
"What is all knowledge too but recorded experience, and a product of history..." (Essays)

Iris Chang:
"I have certainly amassed many historical research gathering skills." (Brainy Quote)

Georg W. F. Hegel:
"History, is a conscious, self-meditating process - Spirit emptied out into Time; but this externalization, this kenosis, is equally an externalization of itself; the negative is the negative of itself... Thus absorbed in itself, it is sunk in the night of its self-consciousness; but in that night its vanished outer existence is preserved, and this transformed existence - the former one, but now reborn of the Spirit's knowledge - is the new existence, a new world and a new shape of Spirit." (The Phenomenology of Spirit, 1807)

John Maynard Keynes:
"The great events of history are often due to secular changes in the growth of population and other fundamental economic causes, which, escaping by their gradual character the notice of contemporary observers, are attributed to the follies of statesmen or the fanaticism of atheists." (The Economic Consequences of the Peace, 1919)

Ibn Khaldun:
"Throughout history many nations have suffered a physical defeat, but that has never marked the end of a nation. But when a nation has become victim of a psychological defeat, then that marks the end of a nation." (Muqaddimah, 1377)

Ibn Khaldun:
"The term of life of a dynasty does not normally exceed three generations. For in the first generation are still preserved the characteristic features of rough, uncivilized rural life, such as hard conditions of life, courage, ferocity, and partnership in authority." (AZQuotes.com)

Bertrand Russell:
"Historical facts, many of them, have an intrinsic value, a profound interest on their own account, which makes them worthy of study, quite apart from any possibility of linking them together by means of causal laws." (On History, 1904)

Thucydides:
"On the whole, however, the conclusions I have drawn from the proofs quoted may, I believe, safely be relied on. Assuredly they will not be disturbed either by the lays of a poet displaying the exaggeration of his craft, or by the compositions of the chroniclers that are attractive at truth's expense." (History of the Peloponnesian War)

Thucydides:
"So little pains do the vulgar take in the investigation of truth, accepting readily the first story that comes to hand." (History of the Peloponnesian War)

Thucydides:
"On the one hand, the friend who is familiar with every fact of the story may think that some point has not been set forth with that fullness which he wishes and knows it to deserve; on the other, he who is a stranger to the matter may be led by envy to suspect exaggeration if he hears anything above his own nature." (History of the Peloponnesian War)

Bernard Williams:
"Those who say that all historical accounts are ideological constructs (which is one version of the idea that there is really no historical truth) rely on some story which must itself claim historical truth... Such an account as a particular piece of history, may very well be true, but truth is a virtue that is embarrassingly unhelpful to a critic who wants not just to unmask past histories of the U.S. but to tell us that at the end of the line there is not historical truth. It is remarkable how complacent some 'deconstructive' histories are about the status of the history that they deploy themselves." (Truth and Truthfulness, 2002)

18. Holism

Robert Boyle:
"The requisites of a good hypothesis are: that it be intelligible. That it neither assume nor suppose anything impossible, unintelligible, or demonstrably false. That it be consistent with itself. That it be lit and sufficient to explicate the phaenomena, especially the chief. That it be, at least, consistent, with the rest of the phaenomena it particularly relates to, and do not contradict any other known phaenomena of nature, or manifest of physical truth." (Quoted in Divulging of Useful Truths in Physick by Barbara Kaplan)

Rudolf Carnap:
"If one is interested in the relations between fields which, according to customary academic divisions, belong to different departments, then he will not be welcomed as a builder of bridges, as he might have expected, but will rather be regarded by both sides as an outsider and troublesome intruder." (Goodreads.com)

Richard Feynman:
"We make not apologies for making these excursions into other fields, because the separation of fields, as we have emphasized, is merely a human convenience, and an unnatural thing. Nature is not interested in our separations and many of the interesting phenomena bridge the gaps between fields." (The Feynman Lectures of Physics, 1964)

Richard Feynman:
"Each piece, or part, of the whole of nature is always merely an approximation to the complete truth so far as we know it." (The Feynman Lectures of Physics, 1964)

Heraclitus:
"It is wise to listen, not to me but to the word and to confess that all things are one." (Fragment 50)

David Hilbert:
"Mathematical science is in my opinion an indivisible whole, an organism whose vitality is conditioned upon the connection of its parts." (Brainyquote.com)

Soren Kierkegaard:
"Above all, every science must vigorously lay hold of its own beginning and not live in complicated relations with other sciences." (Concept of Anxiety, 1844)

Michael C. Jackson:
"There exists an alternative to reductionism for studying systems. This alternative is known as holism. Holism considers systems to be more than the sum of their parts. It is of course interested in the parts and particularly the networks of relationships between the parts, but primarily in terms of how they give rise to and sustain in the existence the new entity that is the whole..." (Systems Thinking: Creative Holism for Managers, 2003)

John Maynard Keynes:
"The paradox finds its explanation, perhaps, in that the master-economist must possess a rare combination of gifts. He must reach a high standard in several different directions and must combine talents not often found together. He must be mathematician, historian, statesman, philosopher – in some degree. He must understand symbols and speak in words. He must contemplate the particular in terms of the general, and touch abstract and concrete in the same flight of thought. He must study the present in the light of the past for the purposes of the future." (Essays In Biography, 1933)

Joseph Needham:
"The hierarchy of relations, from the molecular structure of carbon to the equilibrium of the species and ecological whole, will perhaps be the leading idea of the future." (Brainy Quote)

Otto Neurath:
"For him there is but one science with subdivisions - a unified science of sciences." (Physicalism: The Philosophy of the Viennese Circle, 1931)

Otto Neurath:
"The attempt to construct a fundamental taxonomy of the sciences encounters great difficulty. For instance, logicians and mathematicians disagree among themselves about the objects of their respective research; there is no agreement on the relation of theoretical physics to empirical knowledge and to mathematics." (Protocol Statements, 1932)

Otto Neurath:
"At first the Vienna Circle analyzed 'physics' in a narrow sense almost exclusively; now psychology, biology, sociology. The task of this movement is unified science and nothing less." (Physicalism, 1931)

Linus Pauling:
"It is structure that we look for whenever we try to understand anything. All science is built upon this search..." (The Place of Chemistry in the Integration of the Sciences, 1950)

Max Planck:
"No matter where and how far we look, nowhere do we find a contradiction between religion and natural science." (Religion and Natural Science, 1937)

19. Infinity

Georg Cantor:
"I am so in favor of the actual infinite that instead of admitting that nature abhors it, as is commonly said, I hold that nature makes frequent use of it everywhere, in order to show more effectively the perfections of its author." (Quoted in Out of the Mouths of Mathematicians by Rosemary Schmalz)

Georg Cantor:
"The actual infinite arises in 3 contexts: first when it is realized in the most complete form, in a fully independent otherworldly being, in Deo, where I call it the absolute infinity or simply absolute; second when it occurs in the contingent, created world; third when the mind grasps it in abstracto as a mathematical magnitude, number or order type." (Quoted in Mind Tools by Rudy Rucker)

Georg Cantor:
"Thus I believe that there is no part of matter which is not - I do not say divisible - but actually divisible; and consequently the least particle ought to be considered as a world full of an infinity of different creatures." (Quoted in Out of the Mouths of Mathematicians by Rosemary Schmalz)

Georg Cantor:
"This view [of the infinite] which I to be the sole correct one, is held by only a few. While possibly I am the very first in history to take the position so explicitly, with all its logical consequences, I know for sure that I shall not be the last!" (Quoted in Journey Through Genius by William Dunham)

Pierre-Simon Laplace:
"All these efforts in the search for truth tend to lead it [the human mind] back continually to the vast intelligence... but from which it will always remain infinitely removed." (Philosophical Essays on Probabilities, 1812)

Antonie van Leeuwenhoek:
"How little do we discover in comparison of those things which now are and forever will be hidden from our sight? The whole of which I am fully persuaded no one will ever be able to dive into, and to explain their causes and effects." (Brainyquote.com)

Philolaus:
"The world's nature is a harmonious compound of infinite and finite elements..." (The Life of Pythagoras)

20. Intuition

Isaac Asimov:
"The true artist is quite rational as well as imaginative and knows what he is doing; if he does not, his art suffers. The true scientist is quite imaginative as well as rational, and sometimes leaps to solutions where reason can follow only slowly; if he does not, his science suffers." (The Roving Mind , 1983)

Gaston Bachelard:
"The subconscious is ceaselessly murmuring, and it is by listening to these murmurs that one hears the truth." (The Poetics of Reverie, 1960)

Henri Bergson:
"Intuition is a method of feeling one's way intellectually into the inner heart of a thing to locate what is unique and inexpressible in it." (Quoted in Flowers in the Desert by Georgia O'Keeffe, 2000)

Henri Bergson:
"Intuition, bound up to a duration which is growth, perceives in it an uninterrupted continuity of unforeseeable novelty; it sees, it knows that the mind draws from itself more than it has, that spirituality consists in just that, and that reality, impregnated with spirit, is creation." (The Creative Mind: An Introduction to Metaphysics, 1934)

Joyce Brothers:
"Trust your hunches. They're usually based on facts filed away just below the conscious level." (Quoted in Words of Wisdom by Safire and Safir)

D. Cappon:
"Intuition has long been associated with the mystic, irrational and paranormal."

Alexis Carrel:
"All great men are gifted with intuition. They know without reasoning or analysis, what they need to know." (Brainy Quote)

Giles Deleuze:
"Intuition is neither a feeling, an inspiration nor a disorderly sympathy but a fully developed method." (AZquotes.com)

John Dewey:
"Intuition alone articulates in the forward thrust of life and alone hold of reality." (Time and Individuality, 1940)

Albert Einstein:
"There is no logical way to the discovery of these elemental laws. There is only the way of intuition which is helped by a feeling for the order lying behind the appearance..." (Preface to Max Planck's Where is Science Going?)

Albert Einstein:
"Prophet or not, what is say is more often felt through intuition than through-through-intellect." (Einstein and the Poet: In Search of the Cosmic Man with William Hermanns)

Albert Einstein:
"Many people think that the progress of the human race is based on experiences of an empirical, critical nature, but I say that true knowledge is to be had only through a philosophy of deduction. For it is intuition that improves the world, not just following a trodden path of thought. Intuition makes us look at unrelated facts and then think about them until they can all be brought under one law. To look for related facts means holding onto what one has instead of searching for new facts. Intuition is the father of new knowledge, while empiricism is nothing but an accumulation of old knowledge." (Quoted in Einstein and the Poet by William Hermanns)

Albert Einstein:
"There will come a point in everyone's life, however, where only intuition can make the leap ahead, without ever knowing precisely how." (Einstein and the Poet: In Search of the Cosmic Man with William Hermanns)

Albert Einstein:
"I think that only daring speculation can lead us further and not accumulation of facts." (Letter to Michele Besso, 1952)

Albert Einstein:
"A new idea comes suddenly and in a rather intuitive way. But intuition is nothing but the outcome of earlier intellectual experience." (Letter to H. L. Gordon, 1949)

Sigmund Freud:
"The unconscious is the larger circle which includes within itself the smaller circle of conscious; everything conscious has its preliminary step in the unconscious..." (Dream Psychology: Psychoanalysis for Beginners, 1920)

Sigmund Freud:
"The poets and philosophers before me discovered the unconscious; what I discovered was the scientific method by which the unconscious can be studied." (Quoted in The Liberal Imagination by Lionel Trilling)

Sigmund Freud:
"The conscious mind may be compared to a fountain playing in the sun and falling back into the great subterranean pool of subconscious from which it rises." (Quoted in Bittersweet Destiny: The Story Evolution of Human by Del Theissen)

Northrop Frye:
"I give the impression of elusiveness sometimes, and rightly, because I really do have an inner chamber in my temple I'm not mature enough to open." (Late Notebooks, 1982-1990)

Mahatma Gandhi:
"For it is a think beyond the grasp of reason. It transcends reason... I would have you brush aside all rational explanations and begin with a simple childlike faith in God." (Young India, 1931)

Carl Friedrich Gauss:
"Dark are the paths which a higher hand allows us to traverse here... let us hold fast to the faith that a finer, more sublime solution of the enigmas of earthly life will be present, will become part of us." (Letter to Schumacher, 1823)

Vincent van Gogh:

"Quick work doesn't mean less serious work, it depends on one's self confidence and experience... I must warn you that everyone will think that I work too fast. Don't you believe a word of it. Is it not emotion, the sincerity of one's feeling for nature, that draws us, and if the emotions are sometimes so strong that one works without knowing one works, when sometimes the strokes come  with a continuity and coherence like words in a speech or letter, then one must remember that it has not always been so, and that in time to come there will again be hard days, empty of inspiration. One must strike while the iron is hot and put the forged bars on the side." (Goodreads.com)

Robert Graves:
"Intuition is the supra-logic that cuts out all routine processes of thought and leaps straight from the problem to the answer." (Quoted in Coaching the Mental Game by Dofman and Tosca)

Sam Harris:
"The problem with faith, is that it really is a conversation stopper. Faith is a declaration of immunity to the powers of conversation. It is reason, why you do not have to give reasons, for what you believe." (The View from the End of the World, 2005)

Aldous Huxley:
"Children are remarkably for their intelligence and ardor, for their curiosity, their intolerance of shams, the clarity and ruthlessness of their vision." (Fanatically Formative: Successful Learning During the Crucial K-3 Years)

William James:
"Abstract rules indeed can help; but they help the less in proportion as our intuitions are more piercing, and our vocation is the stronger for the moral life. For every real dilemma is in literal strictness a unique situation..." (The Will to Believe and Other Essays in Popular Philosophy, 1897)

William James:
"The higher and lower feelings, the useful and the erring impulses, begin by being a comparative chaos within us - they must end by forming a stable system of functions in right subordination. Unhappiness is apt to characterize the period of order making and struggle." (The Varieties of Religious Experience, 1903)

Carl Jung:
"We should not pretend to understand the world only by intellect; we apprehend it just as much by feeling. Therefore, the judgement of the intellect is, at best, only the half of truth, and must, if it be honest, also come to an understanding of its inadequacy." (Psychological Types, 1921)

Immanuel Kant:
"Intuitions and concepts constitute... the elements of all our knowledge, so that neither concepts without an intuition in some way corresponding to them, not intuition without concepts can yield knowledge." (Quoted in Twelve Great Philosophers by Wayne Pomerleau)

Immanuel Kant:
"All thought must, directly or indirectly, by way of certain characters, relate ultimately to intuitions and therefore, with us, to sensibility, because in no other way can an object be give to us." (Critique of Pure Reason, 1781)

Immanuel Kant:
"Thoughts without content are empty, intuitions without concepts are blind. The understanding can intuit nothing, the senses can think of nothing. Only through their unison can knowledge arise." (Critique of Pure Reason, 1781)

Soren Kierkegaard:
"Faith does not result from straightforward scholarly deliberation, nor does it come directly; on the contrary in this objectivity one loses that infinite personal, impassioned interstedness, which is the condition of faith, the everywhere and nowhere in which faith can come into existence." (Concluding Unscientific Postscript to Philosophical Fragments, 1846)

Jacques Lacan:
"The unconscious is structured like a language." (AZQuotes.com)

Jacques Lacan:
"The knowledge that there is a part of the psychic functions that are out of conscious reach, we did not need to wait for Freud to know this!" (AZQuotes.com)

Jacques Lacan:
"Discontinuity, then, is the essential form in which the unconscious first appears to us as a phenomenon - discontinuity, in which something is manifested as a vacillation." (The Four Fundamental Concepts of Psycho Analysis, 1978)

Jacques Lacan:
"As is known, it is in the realm of experience inaugurated by psychoanalysis that we may grasp along what imaginary lines the human organism, in the most intimate recesses of its being, manifests its capture in a symbolic dimension." (AZQuotes.com)

Peter Miller, Martin Robson:
"Jung legitimized intuition to some extent through defining the four basic psychological functions as intuition, thinking, feeling and sensation..." (Australian Elite Leaders and Intuition, 2006)

Jawaharal Nehru:
"A leader or a man of action in a crisis almost always acts subconsciously and then thinks of the reasons for their action." (Autobiography, 1936)

Wolfgang Pauli:
"The deepest pleasure in science comes from finding an instantiation, a home, for some deeply felt, deeply held image." (Wikiquote)

Charles Sanders Peirce:
"Feeling which has not yet emerged into immediate consciousness is already affectible and already affected." (The Law of Mind, 1892)

Henri Poincare::
"It is by logic that we prove, but by intuition that we discover. To know how to criticize is good, to know how to create is better." (Science and Method, 1908)

Henri Poincare:
"...mathematical reasoning has itself a sort of creative virtue and consequently differs from a syllogism." (Science and Hypothesis, 1901)

Arthur Schopenhauer:
"The fundament upon which all our knowledge and learning rests is inexplicable." (Counsels and Maxims, 1951)

21. Inventions

Marvin Minsky:
"Most adults have some childlike fascination for making and arranging larger structures out of  smaller ones." (Music, Mind and Meaning, 1981)

Louis Pasteur

"There does not exist a category of science to which one can give the name applied science. There are sciences and the applications of science, bound together as the fruit of the tree which bears it." (Revue Scientifique, 1871)

22. Literature

Isaac Asimov:
"Books... hold within them the gathered wisdom of humanity, the collected knowledge of the world's thinkers, the amusement and excitement built up by the imaginations of brilliant people. Books contain humor, beauty, wit, emotion, thought, and, indeed, all of life. Life without books is empty." (Puzzles of the Black Widowers, 1990)

Francis Bacon:
"Reading maketh a full man, conference a ready man, and writing an exact man." (Essays, 1625)

Thomas Carlyle:
"Literature is the thought of thinking souls." (Essays, Memoirs of the Life of Scott)

William Ellery Channing:
"A beautiful literature springs from the depth and fullness of intellectual and moral life, from an energy of thought and feeling, to which nothing, as we believe, ministers so largely as enlightened religion." (Quoted in Dictionary of Burning Words by Josiah Hotchkiss Gilbert, 1895)

William Ellery Channing:
"God be thanked for books! They are the voices of the distant and the dead, and make us heirs of the spiritual life of past ages." (Quoted in Dictionary of Burning Words by Josiah Hotchkiss Gilbert, 1895)

Giles Deleuze:
"To write is to struggle and resist; to write is to become; to write is to draw a map: I am a cartographer." (Foucault, 1986)

Jacques Derrida:
"A text remains, however, harbored int he inaccessibility of a secret; it is simply that they can never be booked, in the present, into anything that could rigorously be called a perception." (Dissemination, 1972)

Jacques Derrida:
"...to put it playfully and with a certain immodesty, one has not yet begun to read me... even though there are, to be sure, many very good readers." (Learning to Live Finally: The Last Interview, 2007)

Jacques Derrida:
"There is no outside-text." (Wikiquote.com)

Northrop Frye:
"The simple point is that literature belongs to the world man constructs, not the world he sees." (The Educated Imagination, 1963)

Northrop Frye:
"Every human society possesses a mythology which is inherited, transmitted and diversified by literature." (The Critical Path and Other Writings on Critical Theory, 1963-1975)

Northrop Frye:

"This story of loss and regaining of identity is, I think, the framework of all literature." (The Educated Imagination, 1963)

Franz Kafka:
"I think we ought to read only the kind of books that wound and stab us. If the book we are reading doesn't wake us up with a blow on the head, what are we reading it for? ...we need the books that affect us like a disaster, that grieve us deeply, like the death of someone we loved more than ourselves, like being banished into forests far from everyone, like a suicide. A book must be the axe for the frozen sea inside us." (1904, Letter to Oskar Pollack)

Soren Kierkegaard:
"Take a book, the poorest one written, but read it with the passion that it is the only book you will read-ultimately you will read everything out of it, that is, as much as there was in yourself, and you could never get more out of reading, even if you read the best of books." (Stages on Life's Way, 1845)

Gottfried Wilhelm Leibniz:
"I am convinced that the unwritten knowledge scattered among men of different callings surpasses in quantity and in importance anything we find in books, and that the greater part of our wealth has yet to be recorded." (Discours touchant la méthode de la certitude et de l'art d'inventer, 1688)

George Henry Lewes:
"[The great writer] knows how to blend vividness with vagueness, knows where images are needed and where by their vivacity they would be obstacles to the rapid appreciation of thought." (The Principles of Success in Literature, 1865)

George Henry Lewes:
"The magic of the pen lies in the concentration of your thoughts upon one object." (AZquotes.com)

George Henry Lewes:


"An energetic crudity, even a riotous absurdity, has more promise in it than a clever and elegant mediocrity because it shows that the young man is speaking out of his own heart, and struggling to express himself in his own way rather than in the way he finds other men's books." (The Principles of Success in Literature, 1865)

Michel de Montaigne:
"It is more of a job to interpret the interpretations than to interpret the things, and there are more books about books than about any other subject: we do nothing but write glosses about each other." (Essais, 1580)

Friedrich Nietzsche:
"My problems are new, my psychological horizon frighteningly comprehensive, my language bold and clear; there may well be no books written in German which are richer in ideas and more independent than mind." (Letter to Carl Fuchs, 1887)

Friedrich Nietzsche:
"Philsophers' error. - The philosopher supposes that the value of his philosophy lies in the whole, in the structure; but posterity finds its value in the stone which he used for building, and which is used many more times after that for building - better. Thus it finds the value in the fact that the structure can be destroyed and nevertheless retains value as building material." (Mixed Opinions and Maxims, 1879)

Friedrich Nietzsche:
"The worst readers are those who proceed like plundering soldiers; they pick up a few things they can use, soil and confuse the rest, and blaspheme the whole." (Mixed Opinions and Maxims, 1879)

Richard Palmer:
"Hermeneutics, defined as the study of the understanding of the works of man, transcends linguistic forms of interpretation. It's principles apply not only to works in written form but to any work of art." (Theory in Schleiermacher, Dilthey, Heidegger and Gadamer, 1969)

Fernand de Saussure:
"Writing obscures language; it is not a guise for language but a disguise." (Cours de Linguistique Generale, 1916)

Arthur Schopenhauer:

"Reading is merely a surrogate for thinking for thinking for yourself; it means letting someone else direct your thought. Many books moreover, serve merely to show how many ways there are of being wrong, and how far astray you yourself would go if you followed their guidance." (Counsels and Maxims, 1951)

Simone Weil:
"It is not only in literature that fiction generates immortality. It does it also in life itself. For the substance of our life is almost exclusively composed of fiction." (On Science, Necessity and the Love of God, 1968 posthumous)

23. Logic

A. J. Ayer:
"In other words, the propositions of philosophy are not factual, but linguistic in character... Accordingly, we may say that philosophy is a department of logic. For we will see that the characteristic mark of a purely logical enquiry, is that it is concerned with the formal consequences of our definitions and not with questions of empirical fact." (AZquotes.com)

Francis Bacon:
"Aristotle... a mere bond-servant to his logic, thereby rendering it contentious and well nigh useless." (Rerum Novarum, 1605)

Francis Bacon:
"The logic now in use serves rather to fix and give stability to the errors which have their foundation in commonly received notions than to help the search for truth. So it does more harm than good." (Novum Organum, 1620)

George Boole:
"A successful attempt to express logical propositions by symbols, the laws of whose combinations should be found upon the laws of the mental processes which they represent, would, so far, be a step towards a philosophical language." (The Mathematical Analysis of Logic, 1847)

George Boole:
"They who are acquainted with the present state of symbolic algebra, are aware, that the validity of the process of analysis does not depend upon the interpretation of the symbols as they are employed, but solely on the laws of their combination." (The Mathematical Analysis of Logic, 1847)

George Boole:
"There is not only a close analogy between the operations of the mind in general reasoning and its operation int he particular science of algebra, but there is to a considerable extent an exact agreement in the laws by which the two classes of operations are conducted." (An Investigation into the Laws of Thought, 1854)

George Boole:
"That to the existing forms of analysis a quantitative interpretation is assigned, is the result of the circumstances by which those forms were determined, and is not to be construed into a universal condition of analysis. It is upon the foundation of this general principle, that I purpose to establish the calculus of logic..." (The Mathematical Analysis of Logic, 1847)

George Boole:
"I am fully assured, that no general method for the solution of questions in the theory of probabilities can be established which does not explicitly recognize, not only the special numerical bases of the science, but also those universal laws of thought which are the basis of all reasoning, and which, whatever they may be as to their essence, are at least mathematical as to their form." (Solution of a Question in the Theory of Probabilities, 1853)

George Boole:
"The design of the following treatise is to investigate the fundamental laws of those operations of the mind by which reasoning is performed; to give expression to them in symbolical language of a calculus, and upon this foundation to establish the science of logic and construct its method; to make that method itself the basis of a general method for the application of the mathematical doctrine of probabilities; and finally to collect from the various elements of truth brought to view in the course of these inquiries some probable imitations concerning the nature and constitution of the human mind." (An Investigation into the Laws of Thought, 1854)

Rudolf Carnap:
"The function of logical analysis is to analyze all knowledge, all assertions of science and of everyday life, in order to make clear the sense of each assertion and the connections between them. One of the principal tasks of the logical analysis of a given proposition is to find out the method of verification for that proposition." (Philosophy and Logical Syntax, 1935)

Rudolf Carnap:
"If logic ever discusses the truth of factual sentences it does so only conditionally, somewhat as follows: if such-and-such a sentence is true, then such-and-such another sentence is  true. Logic itself does not decide whether the first sentence is true, but surrenders that question to one or the other of the empirical sciences." (Quoted in The Language of Wisdom and Folly by Irving Lee, 1967)

Rudolf Carnap:
"Philosophy is to be replaced by the logic of science - that is to say, by the logical analysis of the concepts and sentences of the sciences,  for the logic of science is nothing other than the logical syntax of the language of science." (Logical Syntax of Language, 1934)

Rudolf Carnap:
"Logic itself does not  decide whether the first sentence is true, but surrenders that question to one or the other of the empirical sciences." (Quoted in The Language of Wisdom and Folly by Irving Lee)

Peter Coffey:
"Men reasoned rightly before Aristotle ever formulated a canon of logic. It was, in fact by an analysis of such reasonings that he discovered those canons... (The Science of Logic, 1912)

Charles Caleb Colton:
"Logic is a large drawer, containing some useful instruments that are really useful and to admire the ingenuity with which those that are not so, are assorted and arranged." (Lacon, 1851)

John Dolan:
"Logic misses the point of half the things we ordinarily say and cannot match the insight of the humblest person's common sense." (Inference and Imagination, 1994)

Albert Einstein:
"Pure logical thinking can give us no knowledge whatsoever of the world of experience and terminates in it." (On the Method of Theoretical Physics, 1934)

Gottlob Frege:
"If the task of philosophy is to break the domination of words over the human mind... then my concept notion being developed for these purposes, can be a useful instrument for philosophers... I believe the cause of logic has been advance already by the invention of this concept notation." (Begriffsschift, 1879)

Gottlob Frege:
"This ideography is a 'formula language', that is, a lingua characterica, a language written with special symbols, 'for pure thought', that is, free from rhetorical embellishments, 'modeled upon that of arithmetic', that is, constructed from specific symbols that are manipulated according to definite rules." (Begriffsschrift, 1879)

Gottlob Frege:
"I hope I may claim in the present work to have made it probable that the laws of arithmetic are analytic judgments and consequently a priori. Arithmetic thus becomes simply a development of logic and every preposition of arithmetic a law of logic albeit a derivative one. To apply arithmetic int he physical sciences is to bring logic to bear on observed facts; calculation becomes deduction." (The Foundations of Arithmetic, 1893)

Gottlob Frege:
"The novelty of this book does not lie in the theorems but in the development of the proofs and the foundations of which they are based." (Grundgesetze der Arithmetik, 1893)

Ibn Khaldun:

"Eventually, Aristotle appeared among the Greeks. He improved the methods of logic and systematized its problems and details. He assigned to logic its proper place as the first philosophical discipline and the introduction to philosophy." (1377, Muqaddimah)

Saul Kripke:
"Logical investigations can obviously be a useful tool for philosophy. They must, however, be informed by a sensitivity to the philosophical significance of the formalism and by a generous admixture of common sense, as well as understanding of both the basic concepts and of the technical details of the formal material used." (AZquotes.com)

Tony Lawson:
"Deduction: all ravens are black, therefore the next raven I see is black. Induction: I see six black ravens, therefore all ravens are black. Retroduction is movement from the blackness to the cause of blackness." (Really Reorienting Modern Economics, YouTube 2010)

Tony Lawson:
"Mathematics is very good if you want to do deduction. Go from general to particular. If I say all ravens are black, I can deduce that the next raven I see is black. Mathematics also good for induction. If I've seen 100 black ravens and I infer all ravens are black, I can do it with mathematics." (Confronting Mathematical Models in Economics, YouTube 2014)

Ernst Mach:
"Strange as it may sound, the power of mathematics rests on its evasion of all unnecessary thought and on its wonderful saving of mental operations." (AZquotes.com)

Maurice Merleau-Ponty:
"The function [of objective thinking] is to reduce all phenomena which bears witness to the union of subject and world, putting in their place the clear idea of the object as in itself and of the subject as pure consciousness." (Phenomenology of Perception, 1945)

Marvin Minsky:
"It makes no sense to seek a single best way to represent knowledge - because each particular form of expression also brings its particular limitations. For example, logic based systems are very precise, but they make it hard to do reasoning with analogies. Similarly, statistical systems are useful for making predictions, but do not serve well to represent the reasons why those predictions are sometimes correct." (The Emotion Machine, 2006)

Marvin Minsky:
"For generations, scientists and philosophers have tried to explain ordinary reasoning in terms of logical principles - with virtually no success. I suspect this enterprise failed because it was looking in the wrong direction: common sense works so well because it is an approximation of logic; logic is only a small part of our great accumulation of different, useful ways to chain things together." (The Society of Mind, 1987)

William of Ockham:
"Logic is the most useful tool of all the arts. Without it no science can be fully known." (Summa Logicae, 1323)

Talcott Parsons
"Special emphasis should be laid on this intimate interrelation of general statements about empirical fact with the logical elements and structure of theoretical systems." (Brainy Quote)

Blaise Pascal:
"Logic has borrowed, perhaps, the rules of geometry, without comprehending their force... it does not thence follow that they have entered into the spirit of geometry, and I should be greatly averse... to placing them on a level with that science that teaches the true method of directing reason." (The Art of Persuasion)

Charles Sanders Peirce:
"Few persons care to study logic, because everybody conceives himself to be proficient enough in the art of reasoning already." (1877, Illustrations of the Logic of Science)

Raymond St. James Perrin:
"The science of logic is said to have been originated by Aristotle... Actual reasoning is little dependent upon a knowledge of this science. Some of the greatest feats of reasoning which history occurred before Aristotle was born, before logic was recognized as a science. Logic enables us to compel assent to propositions, rather than to discover truth. In other words, it too often constitutes merely a training in the art of disputation" (The Religion of Philosophy or the Unification of Knowledge, 1885)

Willard van Orman Quine:
"Logic chases truth up the tree of grammar." (Philosophy of Logic, 1970)

Frank Ramsey:
"Following these authorities, I hold that mathematics is part of logic, and so belong to what may be called the logical school as opposed to the formalist and intuitionist schools." (The Foundations of Mathematics, 1925)

Frank Ramsey:
"It is worth pausing for a moment to consider how far our conclusions are affected by considerations which our simplifying assumptions have forced us to neglect." (A Mathematical Theory of Saving, 1928)

Frank Ramsey:
"Logic issues in tautologies, mathematics in identities, philosophy in definitions; all trivial, but all part of the vital work of clarifying and organizing thought." (The Foundations of Mathematics and Other Logical Essays, 1931 posthumous)

Frank Ramsey:
"The chief danger to our philosophy, apart from laziness and woolliness is scholasticism, the essence of which is treating what is vague as if it were precise and trying to fit it into an exact logical category." (Goodreads.com)

Frank Ramsey:
"...I hold that mathematics is part of logic, and so belong to what may be called the logical school as opposed to the formalist and intuitionist schools." (The Foundations of Mathematics, 1925)

Bertrand Russell:
"All traditional logic habitually assumes that precise symbols are being employed. It is therefore not applicable to this terrestrial life but only to an imagined celestial existence... Logic takes us nearer to heaven than other studies." (Quoted in Foundations of Fuzzy Logic by Brian Gaines)

Bertrand Russell:
"The fact that all mathematics is symbolic logic is one of the greatest discoveries of our age; and when this fact has been established, the remainder of the principles of mathematics consists in the analysis of symbolic logic itself." (Principles of Mathematics, 1903)

Bertrand Russell:
"Pure mathematics consists entirely of assertions to the effect that, if such and such proposition is true of anything, then such and such another proposition is true of that thing." (Mathematics and Metaphysics, 1917)

Bertrand Russell:
"The reason that I call my doctrine logical atomism is because the atoms that I wish to arrive at as the sort of last residue in analysis are logical atoms and physical atoms." (The Philosophy of Logical Atomism, 1918)

Bertrand Russell:
"The proof of their identity is, of course, a matter of detail: starting with premises which would be universally admitted to belong to logic and arriving by deduction at results which as obviously belong to mathematics, we find that there is no point at which a sharp line can be drawn, with logic to the left and mathematics to the right." (Wikiquote)

Antoine de Saint-Exupery:
"Pure logic is the ruin of the spirit." (Flight to Arras, 1942)

Ernst Schroder:
"[My aim is] to design logic as a calculating discipline, especially to give access to the exact handling of relative concepts, and, from then on, by emancipation from the routine claims of natural language to withdraw any fertile soil from 'cliche' int he field of philosophy as well. This should prepare the ground for a scientific universal language..." (Quoted in Nineteenth Century Logic Between Philosophy and Mathematics by V. Peckhaus)

John Searle:
"You need to know enough philosophy so that the methods of logical analysis are available to you to be used as a tool." (The Storm Over the University, 1990)

P. F. Strawson:
"Neither Aristotelian nor Russellian rules give the exact logic of any expression of ordinary language; for ordinary language has no exact logic." (On Referring, 1950)

P. F. Strawson:
"It remains to mention some of the ways in which people have spoken misleadingly of logical form. One of the commonest of these is to talk of 'the logical form' of a statement; as if a statement could never have more than one kind of formal power; as if statements could, in respect of their formal powers, be grouped in mutually exclusive classes, like animals at a zoo in respect of their species." (Introduction to Logical Theory, 1952)

Alfred Tarski:
"Logic is justly considered the basis of all other sciences, even if only for the reason that in every argument we employ concepts taken from the field of logic, and that ever correct inference proceeds in accordance with its laws." (Introduction to Logic: And to the Methodology of Deductive Sciences, 1941)

Alfred Tarski:
"There can be no doubt that the knowledge of logic is of considerable practical importance for everyone who desires to think and infer correctly." (Introduction to Logic: And to the Methodology of Deductive Sciences, 1941)

Miguel de Unamuno:
"Logic tends to reduce everything to identities and genera, to each representation having no more than one single and self same content in whatever place, time, or relation it may occur to us." (Tragic Sense of Life, 1913)

Ludwig Wittgenstein:
"Logic takes care of itself; all we have to do is look and see how it does it." (Notebooks 1914-1916)

24. Mathematics a priori

Hannah Arendt:
"It was mathematics, the non-empirical science par excellence, wherein the mind appears to play only with itself, that turned out to be the science of sciences, delivering the key to those laws of nature and the universe that are concealed by appearances." (The Life of Mind, 1971)

A. J. Ayer:
"The principles of logic and mathematics are true simply because we never allow them to be anything else." (Language, Truth and Logic, 1936)

Georg Cantor:
"Mathematics is in its development entirely free and is only bound int he self evident respect that its concepts must both be consistent with each other and also stand in exact relationship, ordered by definitions, to those concepts which have previously been introduced and are already established." (Quoted in From Kant to Hilbert by William Bragg Ewald)

Tobias Dantzig:
"For the trouble with human words is that they possess content, whereas the purpose of mathematics is to construct pure thought." (Number: The Language of Science, 1930)

Rene Descartes:
"When I imagine a triangle, although there is not perhaps and never was in any place in the universe apart from my thought one such figure, it remains true nevertheless that this figure possesses a certain determinant nature, form, or essence, which is immutable and eternal and not framed by me, nor in any degree dependent on my thought." (Meditations on First Philosophy, 1641)

Rene Descartes:
"Even when I still strongly adhered to the objects of sense, I reckoned among the number of the most certain truths those I clearly conceived relating to figures, numbers and other matters that pertain to arithmetic and geometry, and in general to the pure mathematics." (Meditations on First Philosophy, 1641)

Freeman Dyson:
"Heisenberg discovered the true limits of causality in atomic processes, and Godel discovered the limits of formal deduction and proof in mathematics." (The Scientist as Rebel, 2006)

Carl Friedrich Gauss:
"I mean the word proof not in the sense of the lawyers, who set two half proofs equal to a whole one, but in the sense of a mathematician, where ½ proof = 0, and it is demanded for proof that every doubt becomes impossible." (1826, Letter to Heinrich Wilhelm Matthias Olbers)

Immanuel Kant:
"The science of mathematics presents the most brilliant example of how pure reason may successfully enlarge its domain without the aid of experience." (Critique of Pure Reason, 1781)

Felix Klein:
"Mathematics in general is fundamentally the science of self-evident things." (Awendung der Differential-und Integralechnung auf Geometrie, 1920)

John von Neumann:
"It is exceptional that one should be able to acquire the understanding of a process without having previously acquired a deep familiarity with running it, with using it, before one has assimilated it in an instinctive and empirical way… Thus any discussion of the nature of intellectual effort in any field is difficult, unless it presupposes an easy, routine familiarity with that field. In mathematics this limitation becomes very severe." (Quoted in The World of Mathematics by James Roy Newman)

Benjamin Peirce:
"Mathematics is the science which draws necessary conclusions." (Linear Associative Algebra, 1882)

Bertrand Russell:
"Mathematics takes us still from what is human, into the region of absolute necessity, to which not only the world, but every possible world, must conform." (The Study of Mathematics, 1902)

Bertrand Russell:
"I should agree with Plato that arithmetic, and pure mathematics generally, is not derived from perception." (A History of Western Philosophy, 1945)

Baruch Spinoza:
"In the same way as you know that the 3 angles of a triangle are equal to two right angles: that this is sufficient will be denied by no one whose brain is sound..." (Letter to Albert Burgh)

Ian Stewart:
"Mathematics links the abstract world of mental concepts to the real world of physical things without being located in completely in either." (Preface to What is Mathematics? by Couant and Robbins)

William Whewell:
"I do not include the phrase 'inductive sciences' the branches of pure mathematics (geometry, arithmetic, algebra and the like) because as I have elsewhere stated these are not inductive but deductive sciences: they do not infer true theories from observed facts... without the aid of experience." (History of the Inductive Sciences, 1837)

Alfred North Whitehead:
"The science of pure mathematics, in its modern developments, may claim to be the most original creation of the human spirit." (Science and the Modern World, 1925)

25. Mathematics catalogue

John Barrow:
"On this view we recognize science to be the search for algorithmic compressions... it is simplest to think of mathematics as the catalogue of all possible patterns... when viewed in this way, it is inevitable that the world is described by mathematics." (New Theories of Everything, 2007)

Paul Cohen:
"To the average mathematician who merely wants to know that his work is securely based, the most appealing choice is to avoid difficulties by means of Hilbert's Program. Here one regards mathematics as a formal game and one is only concerned with the question of consistency." (Comments of the Foundations of Set Theory, 1971)

A. D'Abro:
"Hilbert and others succeeded in filling the gap by stating explicitly a complete system of postulates for euclidean and non-euclidean geometries alike." (The Evolution of Scientific Though from Newton to Einstein, 1927)

Tobias Dantzig:
"The mathematician may be compared to a designer of garments, who is utterly oblivious of the creatures whom his garments may fit." (Number: The Language of Science, 1930)

Albert Einstein:
"Pure mathematics is, in its way, the poetry of logical ideas." (Obituary for Emmy Noether, 1935)

Richard Feynman:
"So I have often made the hypothesis that ultimately physics will not require a mathematical statement, that in the end the machinery will be revealed, and the laws will turns out to be simple, like the chequer board with all it apparent complexities." (The Character of Physical Law, 1965)

Richard Feynman:
"Mathematics is not just a language. Mathematics is a language plus reasoning. It's like a language plus logic. Mathematics is a tool for reasoning. It's in fact, a big collection of the results of some person's careful thought and reasoning." (The Character of Physical Law, 1965)

Richard Feynman:
"Don't misunderstand me, there are many, many aspects of the world that mathematics is unnecessary for... but we were talking about physics... to not know mathematics is a severe limitation in understanding the world." (The Pleasure of Finding Things Out, 1999)

G. H. Hardy:
"The function of a mathematician, then, is simply to observe the facts about his own intricate system of reality, that astonishingly beautiful complex of logical relations which forms the subject matter of his science, as if he were an explorer looking at a distant range of mountains, and to record the results of his observations in a series of maps, each of which is a bunch of pure mathematics..." (The Theory of Numbers, 1922)

Michio Kaku:
"Mathematics... is the set of all possible self-consistent structures, and there are vastly more logical structures than physical principles." (Hyperspace, 1995)

Tony Lawson:
"A telescope, a microscope, an electron accelerator: they're all tools of analysis. Mathematical models are tools of analysis." (What's Wrong with Modern Economics, YouTube, 2015)

John von Neumann:
"A large part of mathematics which becomes useful developed with absolutely no desire to be useful, and in a situation where nobody could possibly know in what area it would become useful; and there were no general indications that it ever would be so." (The Role of Mathematics in the Sciences and in Society, 1954)

Bertrand Russell:
"...mathematics may be defined as the subject in which we never know what we are talking about, nor whether what we are saying is true." (Recent work on the Principles of Mathematics 1901)

George Fredrick James Temple:
"Pure mathematics is much more than an armory of tools and techniques for the applied mathematician. On the other hand, the pure mathematician has ever been grateful to applied mathematics for stimulus and inspiration." (100 Years of Mathematics: A Personal Viewpoint, 1981)


William Thomson:
"Nothing can be more fatal to progress than a too confident reliance upon mathematical symbols; for the student is only too apt to take the easier course, and consider the formula and not the facts as the physical reality." (Treatise on Natural Philosophy with Peter Guthrie Tait, 1867)

Alan Turing:
"...we are regarding the function of the mathematician as simply to determine the truth or falsity of propositions." (System of Logic Based on Ordinals, 1938)

26. Mathematics everything

Roger Bacon:
"Mathematics is the gate and key of the sciences... Neglect of mathematics works injury to all knowledge, since he who is ignorant of it cannot know the other sciences or the things of this world. And what is worse, men who are thus ignorant are unable to perceive their own ignorance and so do not seek a remedy." (Quoted in Mathematics and the physical world by Morris Kline)

Auguste Comte:
"Every attempt to refer chemical questions to mathematical doctrines must be considered, now and always, profoundly irrational, as being contrary to the nature of the phenomena... but if the employment of mathematical analysis should ever become so preponderant in chemistry (an aberration which is happily almost impossible) it would occasion vast and rapid retrogradation..."  (System of positive polity, 1852)

Auguste Comte:
"Mathematical Analysis is... the true rational basis of the whole system of our positive knowledge." (System of positive polity, 1852)

Charles Darwin:
"I have deeply regretted that I did not proceed far enough at least to understand something of the great leading principles of mathematics, for men thus endowed seem to have an extra sense." (1887, The Life and Letters of Charles Darwin)

Rene Descartes:
"With me, everything turns into mathematics." (Letter to Marin Mersenne, 1638)

Paul Dirac:
"One could perhaps describe the situation by saying that god is a mathematician of a very high order, and he used very advanced mathematics in constructing the universe." (The Evolution of the Physicist's Picture of Nature, 1963)

Paul Dirac:
"God used beautiful mathematics in creating the world." (Quoted in the Cosmic Code by Heinz Pagels)

Paul Dirac:
"It seems to be one of the fundamental features of nature that fundamental physical laws are described in terms of a mathematical theory of great beauty and  power, needing quite a high standard of mathematics for one to understand it. You may wonder: why is nature constructed along these lines?" (The Evolution of the Physicist's Picture of Nature, 1963)

Euclid:
"The laws of nature are but the mathematical thoughts of God." (Elements)

Leonhard Euler:
"Since the fabric of the universe is most perfect and the work of a most wise Creator, nothing at all takes place in the universe in which some rule of maximum or minimum does not appear … there is absolutely no doubt that every affect in the universe can be explained satisfactorily from final causes, by the aid of the method of maxima and minima, as it can be from the effective causes themselves … Of course, when the effective causes are too obscure, but the final causes are readily ascertained, the problem is commonly solved by the indirect method..." (Wikiquote)

Galileo Galilei:
"Mathematics is the language in which God wrote the universe." (Quoted in Statistics: Concepts and Applications by Frank, Althoen)

Galileo Galilei:
"Philosophy is written in this grand book, which stands continually open before our eyes (I say the 'Universe'), but can not be understood without first learning to comprehend the language and know the characters as it is written. It is written in mathematical language, and its characters are triangles, circles and other geometric figures, without which it is impossible to humanly understand a word; without these one is wandering in a dark labyrinth." (1923, Il Saggiatore)

Robert Grosseteste:
"The consideration of lines, angles and figures is of the greatest utility since it is impossible for natural philosophy to be known without them... All causes of natural effects have to be given through lines, angles and figures, for otherwise it is impossible for the reason why (propter quid) to be known in them." (De Lineas, Anguilis et Figuris)

Werner Heisenberg:
"If nature leads us to mathematical forms of great simplicity and beauty - by forms I am referring to coherent systems not one has previously encounter, we cannot help thinking that they are 'true', that they reveal a genuine feature of nature." (Quoted in Bittersweet Destiny by Del Thiessen)

Johannes Kepler:
"...nothing can be known completely except quantities or by quantities. An so it happens that the conclusions of mathematics are certain and indubitable." (Quoted in Joannis Kepleri Astronomi Opera Omnia by Christian Frisch)

Gottfried Wilhelm Leibniz:
"...if controversies were to arise, there would be no more need of disputation between two philosophers than between two calculators. for it would suffice for them to take their pencils in their hands and to sit down at the abacus and say to each other (and if they so wish also to a friend called to help): let us calculate." (Quoted in preface to his New Essays on Human Understanding, 1765)

Ernst Mach:
"The aim of research is the discovery of the equations which subsist between the elements of phenomena." (Popular Scientific Lectures, 1910)

David Marr:
"The critical act in formulating computational theories turns out to be the discovery of valid constraints on the way the world is structured - constraints that provide sufficient information to all the processing to succeed." (Representation and Recognition of the Spatial Organization of 3D Shapes, 1978)

Dmitri Mendeleev:
"I wish to establish some sort of system not guided by chance but by some sort of definite and exact principle." (An Outline of the System of Elements)

Augustus De Morgan:
"During the last two centuries and a half, physical knowledge has been gradually made to rest upon a basis which it had not before. It has become mathematical." (A Budget of Paradoxes, 1872)

Augustus De Morgan:
"Bacon himself was very ignorant of all that had been done by mathematics; and strange to say, he especially objected to astronomy being handed over to the mathematicians." (A Budget of Paradoxes, 1872)

Marcus du Sautoy:
"That despite the incredible complexity of the world we live in, it can all, ultimately, be explained by numbers... when we don't understand the code, the only way we can make sense of the world is to make up stories." (Conclusion in BBC's The Code)

William Thomson:
"Mathematics is the only true metaphysics." (Quoted in The Life of William Thomson by Silvanus Philips Thompson)

William Thomson:
"Do not imagine that mathematics is hard and crabbed, and repulsive to common sense. It is merely the etherealization of common sense." (Quoted in The Life of William Thomson by Silvanus Philips Thompson)

William Thomson:
"I am never content until I have constructed a mechanical model of the subject I am studying." (Baltimore Lectures on Molecular Dynamics and the Wave Theory of Light, 1904)

William Thomson:
"I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely, in your thoughts, advanced to the stage of science, whatever the matter may be." (Lecture on Electrical Units of Measurement, 1883)

Andre Weil:
"It is hard for you to appreciate that mathematics has become so extensive and so complex that it is essential, if mathematics is to stay as a whole and not become a pile of little bits of research, to provide a unifaction,which absorbs in some simple and general theories all the common substrate of the diverse branches if the science, suppressing what is not so useful and necessary, and leaving in tact what is truly the specific detail of each big problem." (Letter written in 1940)

Bernard Williams:
"Positivism... implies the double falsehood that no interpretation is needed, and that it is not needed because the story which the positivist writer tells, such as it is, is obvious. The story he or she tells is usually a bad one, and its being obvious only means that it is familiar." (Truth and Truthfulness, 2002)

27. Mathematics exact

Roger Bacon:
"If in other sciences we should arrive at certainty without doubt and truth without error, it behooves us to place the foundations of knowledge in mathematics." (Opus Majus)

Robert Chambers:
"The study of mathematics, generally, is also of great importance in cultivating habits of exact reasoning; and in this respect it forms a useful auxiliary to logic." (Chamber's Information for the People, 1875)

Rene Descartes:
"Arithmetic and geometry are much more certain than the other sciences because the objects of them are in themselves so simple and clear that they need not suppose anything which experience can call in question, and both proceed by a chain of consequences which reason deduces one from another." (Rules for the Direction of the Mind, 1628)

Freeman Dyson:
"I am acutely aware of the fact that the marriage between mathematics and physics, which was so enormously fruitful in past centuries, has recently ended in divorce." (Missed Opportunities, 1972)

Richard Feynman:
"It is really quite impossible to say anything with absolute precision, unless that thing is so abstracted from the real world as to not represent any real thing... [Pure mathematics] is not precise in any sense if you deal with real objects of the world..." (New Textbooks for the New Mathematics, 1965)

David Hilbert:
"The organic unity of mathematics is  inherent in the nature of this science for mathematics is the foundation of all exact knowledge of natural phenomena." (Mathematical Problems, 1900)

Benoit Mandelbrot:
"...nobody will deny that there is at least some roughness everywhere." (A Theory of Roughness, 2004)

Benoit Mandelbrot:
"Contrary to popular opinion, mathematics is about simplifying life, not complicating it." (The Mis-Behavior of Markets, 2004)

Benoit Mandelbrot:
"Clouds are not spheres, mountains are not cones, coastlines are not circles, and bark is not smooth, nor does lightning travel in a straight line." (The Fractal Geometry of Nature, 1982)

Augustus De Morgan:
"There never has been, and till we see it we never shall believe that there can be, a system of geometry worthy of the name, which has any material departures from the plan laid down by Euclid." (Short Supplementary Remarks on the First Six Books of Euclid's Elements, 1848)

Augustus De Morgan:
"The genius of Laplace was a sledge hammer in bursting purely mathematical obstacles; but, like that useful instrument, it gave neither finish nor beauty to the results." (In Review of Theorie Analytique des Probabilities, 1837)

John von Neumann:
"The calculus was the first achievement of modern mathematics and it is difficult to overestimate its importance. I think it defines more unequivocally than anything else the inception of modern mathematics; and the system of mathematical analysis, which is its logical development, still constitutes the greatest technical advance in exact thinking." (Quoted in Bigeometric Calculus by James Stewart)

John von Neumann:
"If people do not believe that mathematics is simple, it is only because they do not realize how complicated life is." (Remarks at the Association for Computing Machinery Annual Meeting, 1947)

Aldolphe Quetelet:
"The more advanced the sciences have become, the more they have tended to enter the domain of mathematics, which is a sort of center towards which they converge." (Quoted in Essai by Edward Mailly)

Bertrand Russell:
"It seems to me now that mathematics is capable of an artistic excellence as great as that of any music, perhaps greater... because it gives in absolute perfection that combination, characteristic of great art, of godlike freedom, with the sense of inevitable destiny; because in fact, it constructs an ideal world where everything is perfect and yet true." (Letter to Gilbert Murray, 1902)

Erwin Schrodinger:
"Physical laws rest on atomic statistics and are therefore only approximate." (What is Life, 1944)

Leonardo da Vinci:
"There is no certainty in sciences where one of the mathematical sciences cannot be applied, or which are not in relation with these mathematics." (Notebooks of Leonardo da Vinci)

William Whewell:

"An so no force however great can stretch a cord however fine into a horizontal line which which is actually straight." (Elementary Treatise on Mechanics, 1819)

28. Mathematics geometry

Archimedes:
"How many theorems in geometry which have seemed at first impracticable are in time successfully worked out!" (Wikiquote)

Eric Temple Bell:
"The cowboys have a way of trussing up a steer or a pugnacious bronco which fixes the brute so that it can neither move nor think. This is the hog-tie, and it is what Euclid did to geometry." (The Search for Truth, 1934)

John Dee:
"It is by the straight line and the circle that the first and most simple examples and representation of all things may be demonstrated whether such things be either non-existent or merely hidden under nature's veils." (Monas Hieroglyphica, 1564)

Rene Descartes:
"I have resolved to quit only abstract geometry, that is to say, the consideration of questions which serve only to exercise the mind, and this, in order to study another kind of geometry, which has for its object the explanation of the phenomena of nature." (Letter to Marin Mersenne, 1638)

Rene Descartes:
"Thus, all unknown quantities can be expressed in terms if a single quantity, whenever the problem can be constructed by means of circles and straight lines, or by conic sections, or even by some other curve of degree not greater than the third or fourth." (La Géométrie, 1637)

Paul Dirac:
"My research work was based in pictures. I need to visualize things and protective geometry was often most useful e.g. in figuring out how a particular quantity transforms under Lorenz transformation." (Recollections of an Exciting Era Lecture at Vareena, 1971)

Freeman Dyson:
"Euclid... gave his famous definition of a point: 'a point is that which has no parts, or which has not magnitude' ... a point has no existence by itself. It exists only a s apart of the pattern of relationships which constitute the geometry of Euclid." (Infinite in All Directions, 1988)

Freeman Dyson:
"The bottom line for mathematicians is that the architecture has to be right. In all the mathematics that I did, the essential point was to find the right architecture... The problem is the overall design." (Interview with Donald Albers, 1994)

Euclid:
"A line is length without breadth." (AZQuotes.com)

Euclid:
"In right-angled triangles the square on the side subtending the right angle is equal to the squares on the sides containing the right angle." (AZQuotes.com)

Euclid:
"There is no royal road to geometry." (Quoted in Commentary of the First Book of Euclid's Elements by Proclus)

Graham Flegg:
"Geometry is the most visual of the mathematical disciplines." (Numbers: Their History and Meaning, 1983)

Frederik II:
"I have no fault to find with those who teach geometry. That science is the only one which has not produced sects; it is founded on analysis and on synthesis and on the calculus; it does not occupy itself with the probable truth; moreover it has the same method in every country." (Quoted in the Foundations of Geometry and the Non-Euclidean Plane by G. E. Martin)

Auguste Comte:
"We may therefore define Astronomy as the science by which we discover the laws of the geometrical and mechanical phenomena presented by the heavenly bodies." (The Positive Philosophy of Auguste Comte, 1853)

Johannes Kepler:
"Geometry is one and eternal shining in the mind of God. That share in it accorded to humans is one of the reasons that humanity is the image of God." (1618, Harmonics Mundi)

Johannes Kepler:
"Since geometry is co-eternal with the divine mind before the birth of things, god himself served as his own model in creating the world..." (Hamonices Mundi, 1618)

Joseph Louis Lagrange:
"An ancient writer said that arithmetic and geometry are the wings of mathematics; I believe one say without speaking metaphorically that these two sciences are the foundation and essence of all the sciences which deal with quantity." (Dans les Lecons Elementaries sur les Mathematiques, 1795)

Joseph-Louis Lagrange:
"As long as algebra and geometry proceed along separate paths, their advance was slow and their applications limited. But when these sciences joined company, they drew from each other fresh vitality and thenceforward marched on at a rapid pace toward perfection." (Dans Les Lecons Elementaires sur les Mathematiques, 1795)

Joseph-Louis Lagrange:
"We have already various treatises on Mechanics, but the plan of this one is entirely new... The methods that I explain require neither geometrical, nor mechanical, constructions or reasoning, but only algebraical operations in accordance with regular and uniform procedure." (Quoted in Mathematics, from the points of view of the Mathematician and of the Physicist, 1912)

Gottfried Leibniz:
"Only geometry can hand us the thread (which will lead us through) the labyrinth of the continuum’s composition, the maximum and the minimum, the infinitesimal and the infinite; and no one will arrive at a truly solid metaphysics except he who has passed through this (labyrinth)." (1676, Dissertatio Exoterica De Statu Praesenti et Incrementis Novissimis Deque Usu Geometriae)

Thomas Little:
"Now any one who was in the habit of intently studying the heavens would naturally observe that each constellation has two characteristics, the number of stars which compose it and the geometrical figure which they form." (A History of Greek Mathematics, 1921)

Tim Maudlin:
"If the Greeks had had a mind to reduce mathematics to one field their only choice would have been to reduce arithmetic to geometry." (New Foundations for Physical Geometry: The  Theory of Linear Structures, 2014)

Richard von Mises:
"I am prepared to concede without further argument that all the theoretical constructions, including geometry, which are used in the various branches of physics are only imperfect instruments to enable the world of empirical fact to be reconstructed in our minds." (Probability, Statistics and Truth, 1957)

Augustus De Morgan:
"Geometrical reasoning, and arithmetical process, have its own office: to mix the two in elementary instruction, is injurious to the proper acquisition of both." (Trigonometry and Double Algebra, 1849

Blaise Pascal:
"Geometry is almost the only subject as to which we find truths wherein all men agree; and one cause of this is, that geometers alone regard the true laws of demonstration." (Oeuvres)

Benjamin Peirce:
"There is proof enough furnished by every science, but by none more than geometry, that the world to which we have been allotted is peculiarly adapted to our minds, and admirably fitted to promote our intellectual progress." (Ben Yamen's Song of Geometry, 1853)

Benjamin Peirce:
"Geometry, to which I have devoted my life, is honored with the title of the key of the sciences." (Ben Yamen's Song of Geometry, 1853)

Benjamin Peirce:
"I presume that to the uninitiated the formulae will appear cold and cheerless; but let it be remembered that, like other mathematical formulae, they find their origin in the divine source of all geometry." (Linear Associative Algebra, 1982)

Henri Poincare:
"Mathematicians do not study objects, but the relations between objects." (Science and Hypothesis, 1901)

Pythagoras:
"There is geometry in the humming of the strings, there is music in the spacing of spheres." (Quoted in the Mystery of Matter by Louis Young)

William Whewell:
"And so no force however great can stretch a cord however fine into a horizontal line which is actually straight." (Elementary Treatise on Mechanics (1819)

William Whewell:
"We unfold out of the idea of space the propositions of geometry, which are plainly truths of the most rigorous necessity and universality." (Philosophy of the Inductive Sciences, 1840)

29. Mathematics innovation

W. S. Anglin:
"Mathematics is not a careful march down a well cleared highway, but a journey into a strange wilderness, where the explorers often get lost. Rigor should be a signal to the historian that the maps have been made, and the real explorers have gone elsewhere." (Mathematics and History, 1992)

Archimedes:
"Mathematics reveals its secrets only to those who approach it with pure love, for its own beauty." (AZQuotes.com)

Michael Atiyah:
"People think mathematics begins when you write down a theorem followed by a proof. That's not the beginning, that's the end. For me the creative place in mathematics comes before you start to put things down on paper, before you try to write a formula. You picture various things, you turn them over in your mind. You're trying to create, just as a musician is trying to create music, or a poet. " (Quoted in Qunta magazine: Is there one big question that has always guided you?)

Eric Temple Bell:
"Guided only by their feeling for symmetry, simplicity, and generality and an indefinable sense of the fitness of things, creative mathematicians now, as in the past, are inspired by the art of mathematics rather than by any prospect of ultimate usefulness." (Quoted in 777 Mathematical Conversation Starters by John Pillis)

Eric Temple Bell:
"The so-called obvious was repeatedly scrutinized from every angle and was frequently found to be not obvious but false. 'Obvious' is the most dangerous word in mathematics." (Mathematics: Queen and Servant of Science, 1938)

George Boole:
"I presume that few who have paid any attention to the history of the mathematical analysis, will doubt that it has been developed in a certain order, or that that order has been to a great extent necessary - being determined either by steps of logical deduction, or by the successive introduction time for their evolution had arrived." (A Treatise on Differential Equations, 1859)

Georg Cantor:
"The essence of mathematics lies entirely in its freedom." (Quoted in From Kant to Hilbert by William Bragg Ewald)

Tobias Dantzig:
"The progress of mathematics has been most erratic, and... intuition has played a predominant role in it... it was the function of intuition to create new forms..." (Number: The Language of Science, 1930)

Paul Dirac:
"Just by studying mathematics we can hope to make a guess at the kind of mathematics that will come into the physics of the future." (The Evolution of the Physicist's Picture of Nature, 1963)

Paul Dirac:
"I think its a peculiarity of myself that I like to play about with equations, just looking for beautiful mathematical relationships which maybe don't have any physical meaning at all. Sometimes they do." (Interview with Thomas Kuhn, 1963)

Joseph Fourier:
"Profound study of nature is the most fertile source of mathematical discoveries." (The Analytical Theory of Heat, 1878)

Carl Friedrich Gauss:
"When I have clarified and exhausted a subject, then I turn away from it, in order to go into the darkness again." (Brainyquote.com)

Carl Friedrich Gauss:
"Finally, two days ago, I succeeded - not on account of my hard efforts but by the grace of the Lord. Like a sudden flash of lightning, the riddle was solved. I am unable to say what was the conducting thread that connected what I previously knew with what made my success possible." (Quoted in Mathematical Circles Squared by Howard Eves)

G. H. Hardy:
"I believe that mathematical reality lies outside us, that our function is to discover or observe it, and that the theorems which we prove, and which we describe grandiloquently as our 'creations', are simply our notes of our observations." (Goodreads.com)

G. H. Hardy:
"We may say, roughly, that a mathematical idea is 'significant' if it can be connected, in a natural and illuminating way, with a large complex of other mathematical ideas." (Goodreads.com)

G. H. Hardy:
"The mathematician's patterns, like the painter's of the poet's must be beautiful; the ideas, like the colours or the words must fit together in a harmonious way." (Goodreads.com)

David Hilbert:
"A mathematical problem should be difficult in order to entice us, yet not completely inaccessible, lest it mock at our efforts. It should be to us a guide post on the mazy paths to hidden truths, and ultimately a reminder of our pleasure in the successful solution." (1900, Mathematical Problems)

David Hilbert:
"The further a mathematical theory is developed, the more harmoniously and uniformly does its construction proceed, and unsuspected relations are disclosed between hitherto separated branches of the science." (Brainyquote.com)

Robert Langlands:
"What I have achieved has been largely a matter of chance. Many problems I though about at length with no success. With other problems, there was an inspiration - indeed, some that astound me today. Certainly the best times were when I was alone with mathematics free of ambition and of pretense and indifferent to the world." (Mathematical Retrospections, 2013)

Immanuel Kant:
"Philosophical knowledge is the knowledge gained by reason from concepts; mathematical knowledge is the knowledge gained by reason from the construction of concepts." (Critique of Pure Reason, 1781)

John Stuart Mill:
"Newton saw the truth of many propositions of geometry without reading the demonstrations, but not, we may be sure without their flashing through his mind. A truth, or supposed truth, which is really the result of a very rapid inference may seem to be apprehended intuitively." (A System of Logic, 1843)

Maryam Mirzakhani:
"The beauty of mathematics only shows itself to more patient followers." (Quoted in an interview with the Guardian, 2014)

Augustus De Morgan:
"The moving power of mathematical invention is not reasoning but imagination." (Quoted in The Life of Sir William Rowan Hamilton by Robert Perceval Graves)

John von Neumann:
"Young man, in mathematics you don't understand things. You just get used to them." (Quoted in The Dancing Wu Li Masters by Gary Zukav)

Roger Penrose:
"If you come from mathematics, as I do, you realize that there are many problems, even classical problems, which cannot be solved by computation alone." (A Conversation with Roger Penrose, New York Times, 1999)

Henri Poincare:
"Does the mathematical method proceed from particular to the general, and, if so, how can it be called deductive?" (Science and Hypothesis, 1901)

Srinivasa Ramanujan:
"I have no university education but I have undergone the ordinary school course. After leaving school, I have been employing the spare time at my disposal to work at mathematics. I have not trodden through the conventional regular course which is followed in a university course, but I a striking out a new path for myself." (Letter to G. H. Hardy, 1913)

Peter Rowlett:
"There is no way to guarantee in advance what pure mathematics will later find in application. We can only let the process of curiosity and abstraction take place, let mathematicians obsessively take results to their logical extremes leaving relevance far behind, and wait to see which topics turn out to be extremely useful. If not, when the challenges of the future arrive, we won't have the right place of seemingly pointless mathematics to hand." (The Unplanned Impact of Mathematics, 2011)

Alan Turing:
"Mathematical reasoning may be regarded rather schematically as the exercise of a combination of two facilities, which we may call intuition and ingenuity... The exercise of ingenuity in mathematics consists in aiding the intuition through suitable arrangements of propositions, and perhaps geometrical figures or drawings." (System of Logic Based on Ordinals, 1938)

Karl Weierstrass:
"...it is true that a mathematician who is not somewhat of a poet will never be a perfect mathematician." (Letter to Sofia Kovalevskaya, 1883)

Andre Weil:
"Every mathematician worthy of the name has experienced the state of lucid exaltation in which one though succeeds another as if miraculously." (The Apprenticeship of a Mathematician, 1992)

30. Mathematics numbers

Raymond Beauregard, John Fraleigh:
"Numbers exists only in out minds. There is no physical entity that is number 1."

Richard Dedekind:
"Numbers are free creations of the human mind; they serve as a means of apprehending more easily and more sharply the difference of things." (Essays on the Theory of Numbers, 1901)

W. E. B. Du Bois:
"When you have mastered numbers, you will in fact no longer be reading numbers, any more than you read words when reading books. You will be reading meanings." (Brainy Quote)

Euclid:
"A prime number is one (which is) measured by a unit alone." (Elements)

Leonard Euler:
"Yet, in fact, as I shall show here with very good reasons, the properties of the numbers known today have been mostly discovered by observation, and discovered long before their truth has been confirmed by rigid demonstrations." (Quoted in Induction and Analogy in Mathematics by George Polya)

Leonard Euler:
"...we should take great care not to accept as true such properties of the numbers which we have discovered by observation and which are supported by induction alone. Indeed, we should use such discovery as an opportunity to investigate more exactly the properties discovered and to prove or disprove them; in both cases we may learn something useful." (Quoted in Induction and Analogy in Mathematics by George Polya)

Leonard Euler:
"Mathematicians have tried in vain to this day to discover some order in the sequence of prime numbers, and we have reason to believe that it is a mystery into which the human mind will never penetrate." (Quoted in Calculus Gems by G. Simmons)

Pierre de Fermat:
"There is scarcely any one who states purely arithmetical questions, scarcely any one who understands them. Is this not because arithmetic has been treated up to this time geometrically rather than arithmetically? ... If they succeed in discovering the proof or solution, they will acknowledge that questions of this kind are not inferior to the more celebrated ones from geometry either for depth or difficulty or method of proof..." (Letter to Frenicle de Bessy, 1657)

Pierre de Fermat:
"It is impossible for any number which is a power greater than the second to be written as a sum of two like powers." (AZQuotes.com)

Pierre de Fermat:
"To divide a cube into two other cubes, a fourth power, or in general any power whatever into two powers of the same denomination above the second is impossible..." (AZQuotes.com)

Pierre de Fermat:
"...given any number which is not a square, there also exists an infinite number of squares such that when multiplied into the given number and unity is added to the product, the result is a square." (Letter to Frenicle de Bessy, 1657)

Gottlob Frege:
"Strictly speaking, it is really scandalous that science has not yet clarified the nature of number. It might be excusable that there is still no generally accepted definition of number if at least there were general agreement on the matter itself. However, science has not even decided on whether number is an assemblage of things, or a figure drawn on the blackboard by the hand of man; whether it is something psychical, about whose generation psychology must give information, or whether it is a logical structure; whether it is created and can vanish, or whether it is eternal." (Uber die Zahlen des Herrn H. Schubert, 1899)

Carl Friedrich Gauss:
"Mathematics is the queen of the sciences and arithmetic the queen of mathematics." (Sartorius von Waltershausen, 1866)

James Gow:
"...it is not surprising if Pythagoras, having learnt in Egypt that number was essential to the exact description of forms and of the relation of forms, concluded that number was the cause of form and so of every other quality. Number, he inferred, is quantity and quantity is form and form is quantity." (A Short History of Greek Mathematics, 1884)

Alexander Grothendieck:
"The introduction of the digit 0 or the group concept was general nonsense too, and mathematics was more or less stagnating for thousands of years because nobody was around to take such childish steps..." (Quoted in Analogy, Concepts and methodologies in Mathematics by Brown and Porter)

G. H. Hardy:
"317 is a prime, not because we think so, or because our minds are shaped in one way rather than another, but because it is, because mathematical reality is built that way." (A Mathematician's Apology, 1941)

Pierre-Simon Laplace:
"It is India that gave us the ingenious method of expressing all numbers by means of ten symbols, each symbol receiving a vale position as well as absolute value; a profound and important idea which appears so simple to us now that we ignore its true merit." (Quoted in Return to Mathematical Circles by Eves)

Gottfrield Wilhelm Leibniz
"Music is a hidden arithmetic exercise of the soul, which does not know that it is counting." (Letter to Christian Goldbach, 1712)

Gottfrield Wilhelm Leibniz
"This miracle of analysis, this marvel of the world of ideas, an almost amphibian object between Being and Non-being that we call the imaginary number." (Quoted in Singularités by Christiane Frémont)

Pierre Louis Maupertiusi:
"It seems that the ancient philosopher made the first attempts at this sort of science, in looking for metaphysical relationships between numbers and material bodies." (Accord de differentes loix de la nature qui avoient jusqu'ici paru incompatibles, 1744)

Richard von Mises:
"Remember that algebra, with all its deep and intricate problems, is nothing but a development of the four fundamental operations of arithmetic." (Probability, Statistics and Truth, 1957)

Augustus De Morgan:
"This mysterious 3.141592... which comes in at every door and window, and down every chimney." (Todayinsci.com)

Nicole Oresme:
"Every measurable thing except number is imagined in the manner of a continuous quantity." (Treatise on the Configuration of Qualities and Motions, 1350)

Francis Wayland Parker:
"The science of arithmetic may be called the science of exact limitation of matter and things in space, force and time." (Talks on Pedagogics, 1894)

Giuseppe Peano:
"No number before zero. The numbers may go on forever, but like the cosmos, they have a beginning." (AZquotes.com)

Giuseppe Peano:
"1. Zero is a number. 2. The immediate successor of any number is also a number. 3. Zero is not the immediate successor of any number. 4. No two numbers have the same immediate successor. 5. Any property belonging to 0 and to the immediate successor of any number that also has that property belongs to all numbers." (Quoted in The Mathematical Philosophy of Giuseppe Peano by Hubert Kennedy, 1963)

Giuseppe Peano:
"In every science, after having analyzed the ideas, expressing the more complicated by means of the more simple, one finds a certain number that cannot be reduced among them, and that one can define no further. These are the primitive ideas of science; it is necessary to acquire them through experience, or through induction; it is impossible to explain them by deduction." (Notations de Logique Mathematique, 1894)

Pythagoras:
"Number is the ruler of forms and ideas, and the cause of gods and daemons." (Quoted in Life of Pythagoras by Iamblichus of Chalcis)

Stephen Toulmin:
"A rationally based arithmetic, by contrast, must concern itself with the ideal and final system of number - concepts , and this will provide a unique intellectual standard or template, for judging all men's earlier and cruder proto-arithmetical creations. The analysis of number concepts must therefore be undertaken using the instruments of logic alone." (Human Understanding, 1972)

John Zerzan:
"Number has only an imposed relationship to what is found in the world." (Why Hope? A Stand Against Civilization, 2015)

31. Mathematics patterns

John Adam:
"From rainbows, river meanders, and shadows to spider webs, honeycombs, and the markings on animal coats, the visible world is full of patterns that can be described mathematically." (Mathematics in Nature: Modeling Patterns in the Natural World, 2006)

John Barrow:
"Where there is life there is a pattern, and where there is a pattern, there is mathematics." (The Artful Universe, 1995)

G. H. Hardy:
"A mathematician, like a painter or a poet, is a maker of patterns. His patterns are more permanent than theirs, it is because they are made with ideas." (A Mathematician's Apology, 1941)

32. Measurement

John Stuart Bell:
"The concept of 'measurement' becomes so fuzzy on reflection that it is quite surprising to have it appearing in physical theory at the most fundamental level..." (Quantum Mechanics, 1981)

A. D'Abro:
"The discovery of rigid objects in nature is of fundamental importance. Without it, the concept of measurement would probably never arise and metrical geometry would have been impossible... As for the physical definition of straightness, it could have been arrived at in a number of ways either by stretching a rope between two points or appealing to the properties of these rigid bodies themselves." (The Evolution of Scientific Though from Newton to Einstein, 1927)

Hermann Grassman:
"I define as a unit any magnitude that can serve for the numerical derivation of a series of magnitudes..." (Ausdehnungslehre, 1844)

James Clerk Maxwell:
"...the history of science shews that even during that phase of her progress in which she devotes herself to improving the accuracy of the numerical measurement of quantities with which she has long been familiar, she is preparing for the materials for the subjugation of new regions, which would have remained unknown if she had been contented with the rough methods of her early pioneers." (The Scientific Papers of James Clerk Maxwell, posthumous)

33. Meditation

Johann Sebastian Bach:
"Ceaseless work, analysis, reflection, writing much, endless self-correction, that is my secret." (AZQuotes.com)

Gaston Bachelard:
"If I were asked to name the chief benefit of the house, I should say: the house shelters day-dreaming, the house protects the dreamer, the house allows one to dream in peace." (The Poetics of Space, 1958)

Alexander Graham Bell:
"You cannot force ideas. Successful ideas are the result of slow growth. Ideas do not reach perfection in a day, no matter how much study is put upon them." (1901, Bell Telephone Talk)

Alexander Graham Bell:
"When I have worked a long time on one thing, I make it a point to bring all the facts regarding it together before I retire." (Interview in How They Succeeded; Bell Telephone Talk, 1901)

Alexander Graham Bell:
"Concentrate all your thoughts upon the work at hand. The sun's rays do not burn until brought to a focus." (Interview in How They Succeeded; Bell Telephone Talk, 1901)

George Berkeley:
"Abstract terms (however useful they may be in argument) should be discarded in meditation, and the mind should be fixed on the particular and the concrete, that is, on the things themselves." (1721, De Motu)


Louis de Broglie:
"After long reflection in solitude and meditation, I suddenly had the idea, during the year 1923, that the discovery made by Einstein in 1905 should be generalised by extending it to all material particles an notably electrons." (Preface to his re-edited PhD Thesis, Recherches sur la theorie des quanta, 1963)

George-Louis Leclerc, Comte de Buffon:

"Genius is nothing else than a great aptitude for patience." (La visite a Buffon, ou Voyage a Montbard)

Anthony van Leeuwenhoek:

"A man has always to be busy with his thoughts if anything is to be accomplished." (Brainy Quote)

George Henry Lewes:
"Everyone who has seriously investigated a novel question, who has really interrogated nature with a view to a distinct answer, will bear me out in saying that it requires intense and sustained effort of imagination." (The Principles of Success in Literature, 1865)

John Locke

"This is that which I think great readers are apt to be mistaken in; those who have read of everything, are thought to understand everything too; but it is not always so. Reading furnishes the mind only with materials of knowledge; it is thinking that makes what we read ours. We are of the ruminating kind, and it is not enough to cram ourselves with a great load of collections ; unless we chew them over again, they will not give us strength and nourishment." (Hand Book : Caution and Counsels)

Dmitri Mendeleev:
"I saw in a dream a table where all the elements fell into place as required. Awakening, I immediately wrote it down." (AZquotes.com)

Wolfgang Amadeus Mozart:
"You know that I immerse myself in music, so to speak - that I think about it all day long - that I like experiments, studying, reflecting." (Goodreads.com)

Wolfgang Amadeus Mozart:

"Neither a lofty degree of intelligence nor imagination nor both together go to the making of genius. Love, love, love, that is the soul of genius." (Goodreads.com)

Isaac Newton:

"I keep the subject constantly before me, and wait until the first dawnings open slowly, by little and little, into a full and clear light." (Quoted in Biographia Britannica)

Rembrandt:

"Try to put well in practice what you already know; and in so doing, you will in good time discover the hidden things which you now inquire about. Practice what you know, and it will help to make clear what now you do not know." (Quoted in a Dictionary of Thoughts)

James Watt:
"I can think of nothing else than this machine." (Wikiquote)

Ludwig Wittgenstein:
"There is no more light in a genius than any other honest man, but he has a particular kind of lens to concentrate this light into a burning point." (Culture and Value, 1980 posthumous)

34. Memory

Archimedes:
"Man has always learned from the past. After all, you can't learn history in reverse." (AZQuotes.com)

Henri Bergson:
"I cannot escape the objection that there is no state of mind, however simple, that does not change every moment, since there is no consciousness without memory, and no continuation of a state without the addition, to the present feeling, of the memory of past moments." (An Introduction to Metaphysics, 1903)

Henri Bergson:
"Without this survival of the past into the present there would be no duration, but only instantaneity." (An Introduction to Metaphysics, 1903)

Henri Bergson:
"The pure present is an ungraspable advance of the past devouring the future. In truth, all sensation is already memory." (Matter and Memory, 1896)

Henri Bergson:
"We seize, in the act of perception, something which outruns perception itself." (Matter and Memory, 1896)

J. Buler:
"Some instances of strength of memory are very surprising." (Coleman v. Wathen, 1793)

Philip Roth:
"Memories of the past are not memories of facts but memories of your imaginings of the facts." (The Facts: A Novelist's  Autobiography, 1988)

35. Metaphysics

Anselm:
"Therefore, lord... believe that you are something than which nothing greater can be thought." (Proslogion)

Anselm:
"O supreme and unapproachable light! O whole and blessed truth, how far art thou from me, who am so near to thee! How far removed art thou from my vision, though I am so near thine! Everywhere thou art wholly present, and I see thee not." (AZQuotes.com)

Anselm:
"But since it is better to have perception or to have omnipotence, to be pitiful or to be without passions, than not to have these attributes; how has Thou perception if Thou art not a body?" (Proslogion)

Anselm:
"I do not endeavor, O Lord, to penetrate thy sublimity, for in no wise do I compare my understanding with that; but I long to understand in some degree thy truth, which my heart believes and loves." (Proslogion)

Thomas Aquinas:
"Now the object of the will, i.e., of man's appetite, is the universal good. This is to be found, not in any creature, but in God alone; because every creature has goodness by participation. Thus God alone can satisfy the will of a human being." (Summa Theologica, 1265-1274)

Thomas Aquinas:
"The image of God always abides in the soul, whether this image be obsolete and clouded over as to amount to almost nothing; or whether it be obscured or disfigured, as is the case with sinners; or whether it be clear and beautiful as is the case with the just." (Summa Theologica, 1265-1274)

Thomas Aquinas:
"...one will observe that all things are arranged according to their degrees of beauty and excellence, and that the nearer they are to God, the more beautiful and better they are." (Sermons on the Apostles' Creed)

Thomas Aquinas:
"Whatever is in motion must be put in motion by another. If that by which it is put in motion be itself put in motion be itself put in motion, then this also must needs be put in motion by another, and that by another again. But this cannot go on to infinity, because then there would be no first mover, and, consequently, no other mover; seeing that subsequent movers move only inasmuch as they are put in motion by the first mover; as the staff moves only because it is put in motion by the hand. Therefore it is necessary to arrive at a first mover, put in motion by no other; and this everyone understands to be God." (Summa Theologica, 1265-1274)

Thomas Aquinas:
"Creation is thus said to be a kind of change, according to the way of understanding, insofar as our intellect accepts one and the same thing as not existing before and afterwards existing." (Summa Theologica, 1265-1274)

Averroes:
"The Law teaches that the universe was invented and created by God, and that it did not come into being by chance or by itself." (On the Harmony of Religions and Philosophy)

Averroes:
"If teleological study of the world is philosophy, and if the Law commands such a study, then the Law commands philosophy." (Quoted in An Introductions to Classical Islamic Philosophy by Oliver Leaman)

Averroes:
"To master this instrument the religious thinker must make a preliminary study of logic, just as the lawyer must study legal reasoning." (Quoted in Classical Arabic Philosophy by Jon McGinnis and David Reisman)

Averroes:
"Philosophers do not claim that God does not know particulars; they rather claim that He does not know them the way humans do. God knows particulars as their Creator whereas humans known them as a privileged creations of God might know them." (Quoted in Voices of Islam: Voices of Change by Vincent Cornell)

Avicenna:
"Prayer is that which enables the soul to realize its divinity. Through prayer human beings worship absolute truth, and seek an eternal reward... Prayer is the worship of the first cause of all things, the supreme ruler of all the world, the source of all strength." (AZQuotes.com)

Avicenna:
"God, the supreme being, is neither circumscribed by space, not touched by time; he cannot be found in a particular direction and his essence cannot change." (Quoted in Readings From Islam by Robert Van der Weyer)

A. J. Ayer:
"...It is possible to be a metaphysician without believing in a transcendent reality; for as we shall see that many metaphysical utterances are due to the commission of logical errors, rather than to a conscious desire on the part of their authors to go beyond the limits of experience." (Goodreads.com)

A. J. Ayer:
"Theism is so confused and the sentences in which God appears so incoherent and so incapable of verifiability or falsifiability that to speak of belief or unbelief, faith or unfaith, is logically impossible." (AZquotes.com)

A. J. Ayer:
"I do not believe in God. It seems to me that theists of all kinds have largely failed to make their concept of a deity intelligible; and to the extent that they have made it intelligible, they have given us no reason to think that anything answers to it." (Goodreads.com)

A. J. Ayer:
"The fact that people have religious experiences is interesting from the psychological point of view, but it does not in any way imply that there is knowledge... unless he can formulate this 'knowledge' in propositions that are empirically verifiable, we may be sure that he is deceiving himself." (AZquotes.com)

Johann Sebastian Bach:
"Like all music, the figured bass should have no other end and aim than the glory of God and the recreation of the soul; where this is not kept in mind there is no true music, but only an infernal clamour and ranting." (Quoted in Bibel und Symbol in den Werken Bachs by Ludwig Prautzsch)

Johann Sebastian Bach:
"I play the notes as they are written, but it is God who makes the music." (Goodreads.com)

Johann Sebastian Bach:
"Music is an agreeable harmony for the honor of God and the permissible delights of the soul." (Goodreads.com)

Johann Sebastian Bach:
"The final aim and reason of all music is nothing other than the glorification of God and the refreshment of the spirit." (Goodreads.com)

Max Born:
"There are metaphysical problems, which cannot be disposed of by declaring them meaningless. For as I have repeatedly said, they are 'beyond physics' indeed and demand an act of faith." (Natural Philosophy of Cause and Chance, 1964)

Martin Buber:
"Some would deny any legitimate use of the word God because it has been misused so much. Certainly it is the most burdened of human words." (I and thou, 1923)

Edward Arthur Burtt:
"The only way to avoid becoming a metaphysician is to say nothing." (The Metaphysical Foundations of Modern Physical Science, 1925)

Albert Camus:
"The absurd is the essential concept and the first truth." (The Myth of Sisyphus and Other Essays , 1942)

Albert Camus:
"The realization that life is absurd cannot be an end, but only a beginning. This is a truth nearly all great minds have taken as their starting point. It is not this discovery that is interesting, but the consequences and rules of action drawn from it." (Review of Nausea by Jean-Paul Sartre, 1938)

Jimmy Carter:
"I think of God as an omnipotent and omniscient presence, a spirit that permeates the universe, the essence of truth, nature, being and life. To me, these are profound and indescribable concepts that seem to be trivialized when expressed in words." (Living in Faith, 2001)

Alan Chalmers:
"Science describes not just the observable world, but also the world that lies beyond the appearances." (What is this thing called Science? 1999)

T'ao Ch'ien:
"God can only set in motion: he cannot control the things he has made." (Substance, Shadow and Spirit)

Catholic Church:
"Endowed with a spiritual soul, with intellect and with free will, the human person is from his very conception ordered to god and destined for eternal beatitude." (The Catechism of the Catholic Church, 1711)

Cicero:
"Not to know what happened before one was born is always to be a child." (De Oratore)

Francis Collins:
"Reason alone cannot prove the existence of God. Faith is reason plus revelation, and the revelation part requires one to think with the spirit as well as with the mind. You have to hear the music, not just read the notes on the page." (Quoted on CNN.com)

Nicolaus Copernicus:
"When, therefore, I had long considered this uncertainty of traditional mathematics, it began to weary me that no more definite explanation of the movement of the world-machine established in our behalf by the best and most systematic builder of all, existed among the philosophers who had studied so exactly in other respects the minutest details in regard to the sphere." (Preface Letter to Pope Paul III)

Richard Dawkins:
"The trouble is that God in this sophisticated, physicist's sense bears no resemblance to the God of the Bible or any other religion." (Extracted from the Nullifidian lecture, 1994)

Rene Descartes:
"Because I cannot conceive god unless as existing, it follows that existence is inseparable from him, and therefore that he really exists." (Meditations on First Philosophy, 1641)

James Dobson:
"Try to analyze [God's] omnipotence is like an amoeba attempting to comprehend the behavior of man." (Quoted in On Reading the Bible by Bill Bradfield)

Freeman Dyson:
"To talk about the end of science is just as foolish as to talk about the end of religion." (Progress in Religion, 2000)

Freeman Dyson:
"I do not make clear any distinction between mind and god. God is what mind becomes when it has passed beyond the scale of our comprehension. God may be either a world-soul or a collection of world-souls. " (Progress in Religion, 2000)

Thomas Edison:
"I do not believe in the God of the theologians; but that there is a supreme intelligence I do not doubt." (Quoted in the Freelance Thinker, 1970)

Euclid:
"Handwriting is a spiritual designing, even though it appears by means of a material instrument." (Goodreads.com)

Ludwig Feuerbach:
"What man calls Absolute Being, his God, is his own being. The power of the object over him is therefore the power of his own being." (The Essence of Christianity, 1841)

Ludwig Feuerbach:
"...atheism - at least in the sense of this work - is the secret of religion itself... in its essence, believes in nothing else than the truth and divinity of human nature." (The Essence of Christianity, 1841)

Sigmund Freud:
"Beauty has no obvious use; nor is there any clear cultural necessity for it. Yet civilization could not do without it." (Civilization and it's Discontents, 1929)

Northrop Frye:
"...there is something about time and space that is not real, and something about us that is." (Fearful symmetry: A Study of William Blake, 1947)

Northrop Frye:
"We have revolutionary thought whenever the feeling 'life is a dream' becomes geared to an impulse to awaken from it." (The Great Code: The Bible and Literature, 1982)

Northrop Frye:
"Man is born lost in a forest. If he is obsessed by the thereness of the forest, he stays lost and goes in circles; if he assumes the forest is not there, he keeps bumping into trees. The wise man looks for the invisible line between 'is' and the 'is not' which is the way through." (Late Notebooks, 1982-1990)

Carl Friedrich Gauss:
"There are problems to whose solution I would attach an infinitely greater importance than to those of mathematics, for example touching ethics, or our relation to God, or concerning our destiny and our future; but their solution lies wholly beyond us and completely outside the province of science." (Quoted in The World of Mathematics J. R. Newman)

Sam Harris:
"I don't know what happens after the physical brain dies. I don't know what the relationship between consciousness and the physical world is. I don't think anyone does know." (Big Think interview, 2007)

Stephen Hawking:
"Even if there is only one possible unified theory, it is just a set of rules and equations. What is it that breathes fire into the equations and makes a universe for them to describe? The usual approach of science of constructing a mathematical model cannot answer the questions of why there should be a universe for the model to describe. Why does the universe go to all the bother of existing?" (1988, A Brief History of Time)

Georg W. F. Hegel:
"The objects of philosophy, it is true, are upon the whole the same as religion. In both the object is truth, in that supreme sense in which God and god God is the truth." (Science of Logic, 1812)

Martin Heidegger:
"Why are there beings at all, and why not rather nothing? That is the question... And yet, we are each touched once, maybe even every now and then, by the concealed power of this question, without properly grasping what is happening to us." (What is Metaphysics? 1929)

Robert Heinlein:
"I've never understood how God could expect his creatures to pick the one true religion by faith - it strikes me as a sloppy way to run the universe." (Stranger in a Strange Land, 1961)

David Hume:
"Epicurus's old questions are yet unanswered. Is he willing to prevent evil, but not able? Then is he impotent? Is he able, but not willing? Then is he malevolent? Is he both able and willing? Whence then is evil?" (Dialogues Concerning Natural Religion, 1779)

David Hume:
"The whole is a riddle, an enigma, an inexplicable mystery. Doubt, uncertainty, suspense of judgement appear the only result of our most accurate scrutiny, concerning this subject." (The Natural History of Religion, 1757)

William James:
"All our scientific and philosophical ideals are altars to unknown gods." (Lecture at Harvard, 1884)

William James:
"Religion, therefore, as I now ask you arbitrarily to take it, shall mean for us the feelings, acts and experiences of individual men in their solitude, so far as they apprehend themselves to stand in relation to whatever they may consider the divine." (The Varieties of Religious Experience, 1903)

William James:
"There are moments of sentimental and mystical experience... that carry an enormous sense of inner authority and illumination when they come. But they come seldom, and they do not come to everyone; and the rest of life makes either no connection with them, or tends to contradict them more than it confirms them." (The Varieties of Religious Experience, 1903)

William James:
"[Religion] becomes an essential organ of our life, performing a function which no other portion of our nature can so successfully fulfill." (The Varieties of Religious Experience, 1903)

William James:
"The saintly character is the character for which spiritual emotions are the habitual centre of the personal energy; and there is a certain composite photograph of universal saintliness, the same in all religions, of which the features can easily be traced." (The Varieties of Religious Experience, 1903)

William James:
"I believe the pragmatic way of taking religion to be the deeper way. It gives it body as well as soul, it makes it claim, as everything real must claim, some characteristic realm of fact as its very own." (The Varieties of Religious Experience, 1903)

Jinasena:
"Some foolish men declare that creator made the world. The doctrine that the world was created is ill advised and should be rejected. If God created the world, where was he before creation? If you say he was transcendent then and needed no support, where is he now? How could God have made this world without any raw material? If you say that made this first and then the world, you are faced with an endless regression." (Mahapurana, 9th cen AD)

Carl Jung:
"We know as little of a supreme being of matter. But there is little doubt of the existence of a supreme being as of matter. The world beyond is reality and experiential fact. We don't understand it." (Letter to Morton Kelsey, 1958)

Carl Jung:
"Metaphysical assertions, however, are statements of the psyche, and are therefore psychological." (Psyche and Symbol, 1958)

Carl Jung:
"For lack of empirical data, I have neither knowledge nor understanding of such forms of being, which are commonly called spiritual... Nevertheless, we have good reason to suppose that behind this veil there exists the uncomprehended absolute object which affects and influences us - and to suppose it even, or particularly, in the case of psychic phenomena about which no verifiable statements can be made." (Memories, Dreams and Reflections, 1963)

Carl Jung:
"It is the role of religious symbols to give meaning to the life of man." (Man and His Symbols, 1964)

Immanuel Kant:
"People like to be honored, so people imagine that God also wants to be honored. They forget that the fulfillment of duty towards men is the only honor adequate to him." (Quoted in German Thought by Karl Hillebrand)

Soren Kierkegaard:
"As soon as I am outside my religious understanding, I feel as an insect with which children are playing must feel, because life seems to have dealt with me so unmercifully." (Stages on Life's Way, 1845)

Soren Kierkegaard:
"Oh, can I really believe the poet's tales, that when one first sees the object of one's love, one imagines one has seen her long ago, that all love like all knowledge is remembrance, that love too has its prophecies in the individual." (On Regine Olsen, 1939)

Soren Kierkegaard:
"Father in heaven, when the thought of thee awakens in our soul, let it not waken as an agitated bird which flutters confusedly about, but as a child waking from sleep with a celestial smile." (The Journals of Søren Kierkegaard, 1847)

Jacques Lacan:
"Desire, a function central to all human experience, is the desire for nothing nameable. And at the same time this desire lies at the origin of every variety of animation." (Goodreads.com)

Gottfried Wilhelm Leibniz:
"...As there are an infinity of possible worlds, there are also an infinity of laws, certain ones appropriate to one; others, to another, and each possible individual of any world involves in its concept the laws of its world." (Quoted in Correspondence between Leibniz and Arnaud by George Montgomery)

Gottfried Wilhelm Leibniz:
"Why is there anything at all rather than nothing whatsoever?" (De Rerum Originatione Radicali, 1967)

Gottfried Wilhelm Leibniz:
"Now as there is an infinity of possible universes in the ideas of God, and as only one of them can exist, there must be a sufficient reason for God's choice, which determines him toward one rather than another. And this reason can be found only in the fitness, or the degrees of perfection, that these worlds contain, since each possible thing has the right to claim existence in proportion to the perfection it involves." (La Monadologie, 1720 posthumous)

Jean-Francois Lyotard:
"I shall call modern that art which... presents the fact that the unpresentable exists. To make visible that there is something which can be conceived and which can neither be seen nor made visible." (Goodreads.com)

Jean-Francois Lyotard:
"The sublime is not mere pleasure as taste is - it is a mixture of pleasure and pain... Confronted with objects that are too big according to their magnitude or too violent according to their power, the mind experiences its own limitations." (Peregrinations Law Form)

James Clerk Maxwell:
"It has been asserted that metaphysical speculation is a thing of the past and that physical science has extirpated it. The discussion of the categories of existence, however does not appear to be in danger of coming to an end in our time, and the exercise of speculation continues as fascinating to every fresh mind as it was in the days of Thales. " (Quoted in The Scientific Papers of James Clerk Maxwell)

Michelangelo:
"Every beauty which is seen here below by persons of perception resembles more than anything else that celestial source from which we all are come." (Quoted in Invitation to Italian Poetry by Luciano Rebay)

John Stuart Mill:
"Questions of ultimate ends are not amenable to direct proof. Whatever can be proved to be good, must be so by being shown to be a means to something admitted to be good without proof." (Utilitarianism, 1861)

John Stuart Mill:
"The art of music is good, for the reason, among others, that it produces pleasure; but what proof is it possible to give that pleasure is good?" (Utilitarianism, 1861)

G. E. Moore:
"If I am asked, 'What is good?' my answer is that good is good, and that is the end of the matter. Or if I am asked 'How is that to be defined?' my answer is that it cannot be defined, and that is all I have to say about it." (Principia Ethica, 1903)

G. E. Moore:
"...if 'good' is defined as something else, it is then impossible either to prove that any other definition is wrong or even to deny such definition." (Principia Ethica, 1903)

G. E. Moore:
"If indeed good were a feeling... then it would exist in time. But that is why to call it so is to commit the naturalistic fallacy. It will always remain pertinent to ask, whether the feeling itself is good; and if so, then good cannot itself be  identical with any feeling." (Principia Ethica, 1903)

G. E. Moore:
"We must not, therefore, be frightened by the assertion that a thing is natural into the admission that it is good; good does not, by definition, mean anything that is natural; and therefore always an open question whether anything that is natural is good." (Principia Ethica, 1903)

Thomas More:
"There are several sorts of religions, not only in different parts of the island, but even in every town; some worshipping the sun, others the moon or one of the planets." (Utopia, 1516)

Wolfgang Amadeus Mozart:
"I choose such notes that love one another." (AZQuotes.com)

Wolfgang Amadeus Mozart:

"God is ever before my eyes. I realize his omnipotence and I fear his anger; but I also recognize his compassion, and his tenderness towards his creatures." (AZQuotes.com)

Thomas Nagel:
"The idea of God seems to be the idea of something that can explain everything else, without having to explain itself. But it's very hard to understand how there could be such a thing." (What Does it All Mean? 1987)

Isaac Newton:
"A heavenly master governs all the world as sovereign of the universe. We are astonished by him by reason of his perfection, we honor him and fall down before him because of his unlimited power." (Quoted in Our Humanist Heritage by George Frater, 2010)

Friedrich Nietzsche:
"Underneath this reality in which we live and have our being another different reality lies concealed..." (The Birth of Tragedy, 1872)

Luca Pacioli:
"The quest for our origin is the sweet fruits' juice which maintains satisfaction in the minds of the philosophers." Quoted in The Golden Ratio by Mario Livio)

Charles Sanders Peirce:
"The word 'God' so 'capitalized' (as we Americans say), is the definable proper name signifying 'ens necessarium; in my belief really creator of all three universes of experience." (A Neglected Argument for the Reality of God, 1908)

Benjamin Peirce:
"What is man? ... What a strange union of matter and mind! A machine for converting material into spiritual force." (AZQuotes.com)

Benjamin Peirce:
"Gentlemen, as we study the universe we see everywhere the most tremendous manifestations of force. In our experience we know of but one source of force, namely will. How then can we help regarding the forces we see in nature as due to the will of some omnipresent, omnipotent being? Gentlemen, there must be a God." (AZQuotes.com)

Roger Penrose:
"I think it is a serious issue to wonder about the other platonic absolutes of beauty and morality." (Brainyquote.com)

Roger Penrose:
"To me the world of perfect forms is primary (as was Plato's own belief). Its existence being almost a logical necessity - and both the other worlds are its shadows." (Shadows of the Mind: A Search for the Missing Science of Consciousness, 1994)

Philolaus:
"The essence of things is eternal; it is a unique and divine nature, the knowledge of which does not belong to man." (The Life of Pythagoras)

Max Planck:
"In other words, the fundamental principles and indispensable postulates of every genuinely productive science are not based on pure logic but rather on the metaphysical hypothesis - which no rules of logic can refute - that there exists an outer world which is entirely independent of ourselves." (Where is Science Going? The Universe in Light of Modern Physics, 1932)

Max Planck:
"Science cannot solve the ultimate mystery of nature and that is because, in the last analysis, we ourselves are part of nature and therefore part of the mystery that we are trying to solve." (Where is Science Going? 1932)

Max Planck:
"We must assume behind this force the existence of a conscious and intelligent spirit. This spirit is the matrix of all matter." (The Nature of Matter, 1944)

Plato:
"Beauty of style, harmony, grace and good rhythm depend on simplicity - mean the true simplicity of a rightly and nobly ordered mind and character..." (The Republic)

Plato:
"Musical training is a more potent instrument than any other, because rhythm and harmony find their way into the inward places of the soul." (The Republic)

John Polkinghorne:
"If the physicists seem to achieve their ends more successfully than the theologians, that is simply a reflection of how much easier science is than theology." (Goodreads.com)

John Polkinghorne:
"Theology differs from science in many respects, because of its different subject matter, a personal God who cannot be put to the test in the way that the impersonal physical world can be subjected to experimental enquiry (AZquotes.com)

John Polkinghorne:
"Theologians have a great problem because they're seeking to speak about God. Since God is the ground of everything that is, there's a sense in which every human inquiry is grist to the teleological mill." (Brainyquote.com)

John Polkinghorne:
"God didn't produce a ready made world. The Creator has done something cleverer than this, making a world able to make itself." (Quarks, Chaos and Christianity, 1995)

John Polkinghorne:
"There is much cloudy unpredictable process throughout the whole of the physical world. It is a coherent possibility that God interacts with the history of creation by means of 'information input' into its open physical process. The causal net of the universe is not drawn so tight as to exclude this possibility. Mere mechanism is dead..." (Quarks, Chaos and Christianity, 1995)

Pythagoras:
"When the wise man opens his mouth, the beauties of his soul present themselves to the view, like the statues in a temple." (Quoted in Pythagorean Ethical Sentences From Stobaeus by Florence Firth)

Pythagoras:
"The most momentous thing in human life is the art of winning the soul to good or to evil." (Quoted in Lives and Opinions of Eminent Philosophers by Diogenes Laertius)

Jean-Jacques Rousseau:
"Our island is this earth; and the most striking object we behold is the sun. As soon as we pass beyond our immediate surroundings, one or both of these must meet our eye. Thus the philosophy of most savage races is mainly directed to imaginary divisions of the earth or to the divinity of the sun." (1762, On Education)

Bertrand Russell:
"Mysticism is, in essence, little more than a certain intensity and depth of feeling in regard to what is believed about the universe." (Mysticism and Logic and Other Essays, 1918)

Carl Sagan:
"Was the Universe devoid of all matter and then matter suddenly somehow created, how did that happen? In many cultures, the customary answer is that a God or Gods created the Universe out of nothing. But if we wish to pursue this question courageously, we must ask the next question: where did God come from? If we decide that this is an unanswerable question, why not save a step and conclude that the origin of the Universe is an unanswerable question?" (Cosmos: A Personal Voyage, 1980)

Carl Sagan:
"In the fabric of space and in the nature of matter, as in a great work of art, there is written small, the artist's signature." (Contact, 1985)

Jean-Paul Sartre:
"Existentialism is nothing else but an attempt to draw the full conclusions from a consistently atheistic position. Its intention is not in the least that of plunging men into despair." (Existentialism Is a Humanism, 1946)

Jean-Paul Sartre:
"The world is sacred because it gives an inkling of a meaning that escapes us." (Saint Genet, Actor and Martyr, 1952)

Friedrich Schelling:
"God, however, as identity of the highest order, remains above all reality and eternally has merely an indirect relationship." (Philosophy and Religion, 1804)

Friedrich Schelling:
"There was a time when religion was kept secret from popular belief within the mystery cults like a holy fire, sharing a common sanctuary with philosophy... At that time philosophers still had the courage and the right to discuss the singly great themes, the only ones worth of philosophizing and rising above common knowledge." (Philosophy and Religion, 1804)

Arthur Schopenhauer:
"There are two things which make it impossible to believe that this world is the successful work of an all-wise, all-good, and, at the same tie, all-powerful Being; firstly the misery which abounds in it everywhere; and secondly the obvious imperfection of its highest product, man, who is a burlesque of what he should be." (On the Sufferings of the World, 1850)

Arthur Schopenhauer:
"The chief objection I have to pantheism is that it says nothing. To call the world 'God' is not to explain it; it is only to enrich our language with a superflous synonym for the word 'world'." (On Pantheism)

Erwin Schrodinger:
"[Science] cannot tell us a word about red and blue, bitter and sweet, physical pain and physical delight; it knows nothing of beautiful and ugly, good or bad, god and eternity. Science sometimes pretends to answer questions in these domains, but the answers are very often silly that we are not inclined to take them seriously." (Nature and the Greeks, 1954)

Erwin Schrodinger:
"Science cannot tell us a word about why music delights us, of why and how an old song can move us to tears." (1958, Mind and Matter)

John Searle:
"Dualism makes the problem insoluble; materialism denies the existence of any phenomenon to study, and hence of any problem." (Consciousness and Language, 2002)

John Searle:
"In the performance of an illocutionary act in the literal utterance of a sentence, the speaker intends to produce a certain effect by means of getting the hearer to recognize his intention to produce that effect; and furthermore, if he is using the words literally, he intends this recognition to be achieved in virtue of the fact that the rules for using the expressions he utters associate the expression with the production of that effect." (Speech Acts: An Essay in the Philosophy of Language, 1969)

Socrates:
"Suppose that there are two sorts of existence, one seen, and the other unseen... the seen is the changing and the unseen is the unchanging... and further, is not one part of us body and the rest of us soul?" (Quoted in Phaedo by Plato)

Baruch Spinoza:
"Whatsoever is, is in God, and without God, nothing can be or be conceived." (Ethica Ordine Geometrico Demonstrata, 1677)

Baruch Spinoza:
"Beauty, my dear Sir, is not so much a quality of the object beheld, as an effect in him who beholds it... The most beautiful hand seen through the microscope will appear horrible. Some things are beautiful at a distance, but ugly near; thus things regarded in themselves, and in relation to God, are neither ugly nor beautiful." (Letter to Hugo Boxel, 1674)

Baruch Spinoza:
"For I hold that God is of all things the cause immanent, as the phrase is, not transient. I say that all things are in God and move in God, thus agreeing with Paul, and, perhaps, with all the ancient philosophers, though the phraseology may be different..." (Letter to Henry Oldenburg, 1675)

Baruch Spinoza:
"God is the Immanent Cause of all things, never truly transcendent from them." (Ethics, 1677)

Baruch Spinoza:
"Individual things are nothing but modifications of the attributes of God, or modes by which the attributes of God are expressed in a fixed and definite manner." (Ethics, 1677)

Baruch Spinoza:
"By God, I mean a being absolutely infinite - that is, a substance consisting in infinite attributes, of which each expresses eternal and infinite essentially." (Ethics, 1677)

Baruch Spinoza:
"Things could not have been brought into being by God in any manner or in any order different from that which has in fact obtained." (Ethics, 1677)

William Thomson:
"We cannot, of course, give a definition of matter which will satisfy the metaphysician, but the naturalist may be content to know matter as that which can be perceived by the senses, or as that which can be acted upon by, or can exert, force." (Treatise on Natural Philosophy with Peter Guthrie Tait, 1867)

Mark Twain:
"We have not the reverent feeling for the rainbow that the savage has, because we know how it is made. We have lost as much as we gained by prying into that matter." (A Tramp Abroad, 1880)

Leonardo da Vinci:
"We, by our arts may be called the grandsons of God." (Quoted by The Notebooks of Leonardo da Vinci by Rudolf Flesch)

Voltaire:
"I can't imagine how the clockwork of the universe can exist without a clockmaker." (Quoted in More Random Walks in Science by Robert Weber)

Voltaire:
"Superstition is to religion what astrology is to astronomy, the mad daughter of a wise mother. There daughters have too long dominated the earth." (Treatise on Toleration, 1763)

Voltaire:
"If this is the best of possible worlds, what then are the others?" (Candide, 1759)

Voltaire:
"All philosophical sects have run aground on the reef of moral and physical ill. It only remains for us to confess that God, having acted for the best, had not been able to do better." (Dictionnaire philosophique, 1785-1789)

Voltaire:
"'If God did not exist, it would be necessary to invent him.' But all nature cries aloud that he does exist: that there is a supreme intelligence, an immense power, an admirable order, and everything teaches us our own dependence on it." (Letter to Prince Frederick William of Prussia, 1770)

Alfred Russel Wallace:
"But whether there be a God and whatever be His nature; whether we have an immortal soul or not, or whatever may be our state after death, I can have no fear of having to suffer for the study of nature and the search for truth..." (Letter to a relative, 1861)

Alan Watts:
"...everyone has a religion, whether admitted or not, because it is impossible to be human without having some basic assumptions (or intuitions) about existence..." (In My Own Way: An Autobiography 1915-1965, 1972)

Max Weber:
"The fate of our times is characterized by rationalization and intellectualization and, above all, by the disenchantment of the world. Precisely the ultimate and most sublime values have retreated from public life either into the transcendental realm of mystic life or into the brotherliness of direct and personal human relations." (Science as a Vocation, 1917)

Simone Weil:
"When as a result of what was called the enlightenment in the 18th century, the priest had in fact almost entirely lost their function as guidance. Their place was taken by writers and scientists. In both cases it is equally absurd. Mathematics, physics and biology are as remote from spiritual guidance as the art of arranging words. When that function is usurped by the literature and science it proves there is no longer any spiritual life." (On Science, Necessity and the Love of God, 1968 posthumous)

Simone Weil:
"There is a reality outside the world, that is to say, outside space and time, outside man's mental universe, outside any sphere whatsoever that is accessible to human faculties. Corresponding to this reality, at the centre of the human heart, is the longing for an absolute good, a longing which is always there and is never appeased by any object in this world." (Draft for a Statement of Human Obligation, posthumous)

Ludwig Wittgenstein:
"What can be said at all can be said clearly and what we cannot talk about we must pass over in silence." (Tractatus Logico-Philosophicus, 1922)

Ludwig Wittgenstein:
"To believe in a God means to understand the question about the meaning of life. To believe in a God means to see that the facts of the world are not the end of the matter. To believe in God means to see that life has meaning." (Notebooks 1914-1916)

Ludwig Wittgenstein:
"There are, indeed things that cannot be put into words. They make themselves manifest. They are what is mystical." (Tractatus Logico-Philosophicus, 1922)

Ludwig Wittgenstein:
"It is not how things are in the world that is mystical, but that it exists." (Tractatus Logico-Philosophicus, 1922)

Ludwig Wittgenstein:
"The way you use the word 'God' does not show whom you mean but rather what you mean." (Culture and Value, 1980 posthumous)

Edward Young:
"A God alone can comprehend a God." (Night Thoughts, 1742)

36. Neuroscience

Paul Churchland:
"Your brain is far too complex and mercurial for its behavior to be predicted in any but the broadest outlines or for any but the shortest distances in the future." (The Engine of Reason, the Seat of the Soul: A Philosophical Journey in the Brain, 1996)

Carl Friedrich Gauss:
"I scarcely believe that in psychology data are present which can be mathematically evaluated. But one cannot know this with certainty without having made the experiment." (Quoted in Titan of Science by Guy Waldo Dunnington)

David Marr:
"To understand the relationship between behavior and brain one has to begin by defining the function or computational goal, of a complete behavior. Only then can a neuroscientist determine how the brain achieves that goal." (Quoted in Decisions, Uncertainty and the Brain by Paul Glimcher, 2004)

Marvin Minsky:
"Unless we can explain the mind in terms of things that have no thoughts, or feelings of their own, we'll only have gone around in a circle." (The Society of Mind, 1987)

John von Neumann:
"When we talk mathematics, we may be discussing a secondary language built on the primary language of the nervous system." (Quoted in Jonn von Neumann by Oxtoby and Pettis)

37. Ockham's razor

Francis Crick:
"What is found in biology is mechanisms, mechanisms built with chemical components and that are often modified by other, later mechanisms added to the earlier ones. While Occam's razor is a useful tool in the physical sciences, it can be a dangerous implement in biology." (What Mad Pursuit, 1988)

Ronald Fisher:
"After all, it is a common weakness of young authors to put too much into their papers." (Contributions to Mathematical Statistics, 1950)

Buckminster Fuller:
"Thinking is a momentary dismissal of irrelevancies." (Utopia or Oblivion: The Prospect of Humanity, 1969)

Carl Friedrich Gauss:
"You know that I write slowly. This is chiefly because I am never satisfied until I have said as much as possible in a few words, and writing briefly takes far more time than writing at length." (Brainyquote.com)

Werner Heisenberg:
"Even for the physicist, the description in plain language will be the criterion of the degree of understanding that has been reached." (Physics and Philosophy, 1958)

David Hilbert:
"Besides it is an error to believe that rigour is the enemy of simplicity. On the contrary we find it confirmed by numerous examples that the rigorous method is at the same time the simpler and more easily comprehend. The very effort for rigour forces us to find out simpler methods of proof." (AZquotes.com)

David Hilbert:
"...it is ingrained in mathematical science that every real advance goes hand in hand with the invention of sharper and simpler methods..." (Mathematical Problems, 1900)

Jonathan Ive:
"I think there is a profound and enduring beauty in simplicity. In clarity. In efficiency. True simplicity is derived from so much more than just the absence of clutter." (Presentation at WWDC 2013 for iOS 7)

John Kenneth Galbraith:
"Do not be alarmed by simplification, complexity is often a device for claiming sophistication, or for evading simple truths." (The Age of Uncertainty, 1977)

Francois de La Rochefoucauld:
"The stamp of great minds is to suggest much in few words; by contrast, little minds have the gift of talking a great deal and saying nothing." (Reflections; or Sentences and Moral Maxims, 1665-1678)

Francois de La Rochefoucauld:
"True eloquence consists in saying all that need be said and no more." (Reflections; or Sentences and Moral Maxims, 1665-1678)

George Henry Lewes:
"There are occasions when the simplest and fewest words surpass in effect all the wealth of rhetorical amplification." (The Principles of Success in Literature, 1865)

George Henry Lewes:
"[The artist] uses the simplest phrases without triviality and the grandest without a suggestion of grandiloquence." (The Principles of Success in Literature, 1865)

Ernst Mach:
"I know of nothing more terrible than the poor creatures who have learned too much... What they have acquired is a spider's web of thoughts too weak to furnish sure supports, but complicated enough to provide confusion." (Popular Scientific Lectures, 1898)

Ernst Mach:
"Science is the most complete presentment of facts with the least expenditure of thought." (AZquotes.com)

Friedrich Nietzsche:
"It is my ambition to say in ten sentences what everyone else says in a whole book - what everyone else does not say in a whole book." (Twilight of the Idols, 1888)

William of Ockham:
"It is pointless to do with more what can be done with fewer." (Summa Totius Logicae)

William of Ockham:
"Plurality is never to be posited without necessity." (Questiones et decisiones in quattuour libros Sententiarum Petri Lombardi)

William of Ockham:
"Simpler explanations are, other things being equal, generally better than more complex ones." (AZQuotes.com)

William of Ockham:
"When you have two competing theories that make exactly the same predictions, the simpler one is the better." (AZQuotes.com)

Enrique Jardiel Poncela:
"When something can be read without effort, great effort has gone into its writing."

Ptolemy:
"We consider it good principle to explain the phenomena by the simplest hypothesis possible." (Quoted in the Science of Conjecture by James Franklin)

Ernest Rutherford
"An alleged scientific discovery has no merit unless it can be explained to a barmaid." (Quoted in Einstein: The Man and His Achievement )

L. K. Samuels:
"Simplicity in a system tends to increase that system's efficiency. Because less can go wrong with fewer parts, less will." (In Defense of Chaos, 2013)

Arthur Schopenhauer:
"From every page and every line, there speaks an endeavor to beguile and deceive the reader, first by producing an effort to dumbfound him, then by incomprehensible phrases and even sheer nonsense to stun and stupefy him, and again by audacity of assertion to puzzle him, in short, to throw dust in his eyes and mystify him as much as possible." (Sketch of a History of the Doctrine of the Ideal and the Real)

John Searle:
"Where questions of style and exposition are concerned I try to follow a simple maxim: if you can't say it clearly you don't understand it yourself." (Intentionality: An Essay in the Philosophy of Mind, 1993)

John Searle:
"You cannot think clearly if you cannot speak and write clearly." (The Storm Over the University, 1990)

Ludwig Wittgenstein:
"Are you a bad philosopher then if what you write is hard to understand? If you were better you would make what is difficult easy to understand but who says that's possible." (Quoted in Wittgenstein: A Wonderful Life documentary)

John Ziman:
"A new scientific theory is seldom stated with such clarity by it original author, and usually takes many years to creep into public consciousness." (The Force of Knowledge: The Scientific Dimension of Society, 1976)

38. Patterns

David Bednar:
"Patterns help to avoid waste and unwanted deviations and facilitate uniformity that is appropriate and beneficial." (Quoted in Elder Bednar Teaches Women the Spiritual pattern of Small and Simple Things by Melissa Merrill)

Werner Callebaut, Diego Rasskin-Gutnam:
"But patterns are also the realm of art and human enterprise thus, we recognize a sense of universality embedded in patterns, which have permeated human culture through an inner necessity to comprehend natural phenomenon." (Modularity: Understanding the Development and Evolution of Natural Complex Systems, 2005)

Anthony Mannucci:
"We forget that the patterns themselves transcend the material world. The patterns are not material objects." (Embrace the Infinite: The science of Spirituality, 2012)

Nicole Oresme:
"The heavenly bodies move with such regularity, orderliness, and symmetry that it is truly a marvel; and they continue always to act in this manner ceaselessly, following the established system, without increasing or reducing speed..." (Le Livre du Ciel et du Monde, 1377)

Chuck Parahniuk:
"What we call chaos is just patterns we haven't recognized. What we call random is just patterns we can't decipher." (Quoted in Principles of Counseling and psychotherapy by Gerald Mozozierz)

Charles Sanders Peirce:
"Uniformities are precisely the sort of facts that need to be accounted for." (The Architecture of Theories, 1891)

Jordan Peterson:
"Imagine that each of these layers of existence are like patterns. They're patterns within patterns..." (Wikiquote)

L. K. Samuels:
"After all, order is merely the repetition of patterns; chaos is the process that establishes those patterns." (Chaos Gets a Bad Rap, 2015)

39. Physics

Archimedes:
"Equal weights at equal distances are in equilibrium and equal weights at unequal distances are not in equilibrium but incline towards the weight which is at the greater distance." (On the Equilibrium of Planes)

Archimedes:
"Two magnitudes whether commensurable or incommensurable, balance at distances reciprocally proportional to the magnitudes." (On the Equilibrium of Planes)

Archimedes:
"It follows at once from the last proposition that the centre of gravity of any triangle is at the intersection of the lines drawn from any two angles to the middle points of the opposite sides respectively." (On the Equilibrium of Planes)

Amedeo Avogadro:
"It must ... be admitted that very simple relations ... exist between the volumes of gaseous substances and the numbers of simple or compound molecules which form them." (Today in Science)

A. D'Abro:
"Kant's knowledge of Newtonian mechanics was extremely poor say the least." (The Evolution of Scientific Thought from Newton to Einstein, 1927)

Max Born:
"I am now convinced that theoretical physics is actually philosophy. It has revolutionized fundamental concepts, e.g. about space and time (relativity), about causality (quantum theory), and about substance and matter (atomists)." (Quoted in Schrodinger: Life and Thought by Walter Moore)

John Dalton:
"Now it is one great object of this work, to shew the importance and advantage of ascertaining the relative weights of the ultimate particles, both of simple and compound bodies..." (A New System of Chemical Philosophy, 1808)

John Dalton:
"The cause of rain is now, I consider, no longer an object of doubt. If two masses of air of unequal temperatures, by the ordinary currents of the winds, are intermixed, when saturated with a vapour, a precipitation ensues." (Quoted in On the Drainage of Lands, Towns and Buildings by Dempsey and Clark)

John Dalton:
"1. Small particles called atoms exist and compose all matter; 2. They are indivisible and indestructible; 3. Atoms of the same chemical element have the same chemical properties and do not transmute or change into different elements." (A New System of Chemical Philosophy, 1808)

John Dalton:
"Matter, though divisible in an extreme degree, is nevertheless not infinitely divisible. That is, there must be some point beyond which we cannot go in the division of matter... I have chosen the word 'atom' to signify these ultimate particles." (Dalton's Manuscript Notes, 1810)

John Dalton:
"...by taking a given volume of any gas, we seem persuaded that, let the divisions be ever so minute, the number of particles must be finite." (A New System of Chemical Philosophy, 1808)

Paul Dirac:
"It therefore becomes desirable that approximate practical methods of applying quantum mechanics should be developed, which can lead to an explanation of the main features of complex atomic systems without too much computation." (Proceedings of the Royal Society of London, 1926)

Paul Dirac:
"Nevertheless, it has been found possible to set up a new scheme, called 'quantum mechanics', which is more suitable for the description of phenomena on the atomic scale and which in some respects more elegant and satisfying than the classical scheme." (The Principles of Quantum Mechanics, 1958)

Paul Dirac:
"Some day a new quantum mechanics, a relativistic one, will be discovered in which we sill not have these infinities occurring at all. It might very well be that the new quantum mechanics will have determinism in the way that Einstein wanted." (Quoted in Albert Einstein: Historical and Cultural Perspectives by Gerald James Holton and Yehuda Elkana)

Freeman Dyson:
"If it should turn out that the whole of physical reality can be described by a finite set of equations, I would be disappointed, I would feel that the creator had been uncharacteristically lacking in imagination." (Infinite in All Directions, 1988)

Freeman Dyson:
"Oppenheimer in his later years believed that the only problem worthy of attention of a serious theoretical physicist was the discovery of the fundamental equations of physics. Einstein certainly felt the same way." (The Scientist as Rebel, 2006)

Freeman Dyson:
"Rutherford did not pretend to understand quantum mechanics but he understood the Gamow formula would give his accelerator a crucial advantage." (The Scientist as Rebel, 2006)

Freeman Dyson:
"In my opinion the black hole is incomparably the most exciting and most important consequence of general relativity. But Einstein... was actively hostile to the idea of black holes... Oddly enough, Oppenheimer too in later life was uninterested in black holes, although... they were his most important contribution to science." (The Scientist as Rebel, 2006)

Arthur Stanley Eddington:
"And so in its actual procedure physics studies not these inscrutable qualities, but pointer readings which we can observe... The former have as much resemblance to the latter as a telephone number has to a subscriber." (Domain of Physical Science, 1925)

Michael Faraday:
"There is no more open door by which you can enter into the study of natural philosophy than by considering the physical phenomena of a candle." (The Chemical History of a Candle, 1860)

Michael Faraday:
"I was at first almost frightened when I saw much mathematical force made to bear upon the subject, and then wondered to see that the subject stood it so well." (Letter to James Clerk Maxwell, 1857)

Michael Faraday:
"It is the great beauty of our science, chemistry, that advancement in it, whether in a degree great or small, instead of exhausting the subjects of research, opens the doors to further and more abundant knowledge, overflowing with beauty and utility." (Experimental Researches in Electricity, 1937)

Enrico Fermi:
"Although the problem of transmuting chemical elements into each other is much older than a satisfactory definition of the very concept of chemical element, it is well known that the first and most important step towards its solution was made only nineteen years ago by the late Lord Rutherford, who started the method of the nuclear bombardments." (Nobel lecture, 1938)

Richard Feynman:
"So I hope you accept nature as she is - absurd." (QED: The Strange Theory of Light and Matter, 1965)

Richard Feynman:
"If it turns out [physics] is like an onion with millions of layers and we're just sick and tired of looking at the layers, then that's the way it is!" (Quoted in No Ordinary Genius by Christopher Sykes)

Stephen Hawking:
"There ought to be something very special about the boundary conditions of the universe and what can be more special than that there is no boundary? (Quoted in The Anthropic Cosmological Principle, 1986)

Galileo Galilei:

"It has been observed that missiles and projectiles described a curve path of some sort; however no one has pointed out the fact that this path is a parabola." (Dialogues and Mathematical Demonstrations Concerning Two New Sciences, 1638)

Galileo Galilei:

"Some superficial observations have been made, as for instance, that the free motion of a heavy falling object is continuously accelerated; but to just what extent this acceleration occurs has not yet been announced." (Dialogues and Mathematical Demonstrations Concerning Two New Sciences, 1638)

Carl Gustav Jacob Jacobi:
"Any progress in the theory of partial differential equations must bring about a progress in mechanics." (Lectures on Dynamics, 1842)

Morris Klein:
"Radio waves and light waves operate in a physical darkness illuminated only for those who would carry the torch of mathematics." (Mathematics and the Physical World, 1959)

Joseph Louis Lagrange:
"Newton was the greatest genius that ever existed, and the most fortunate for we cannot find more than once a system of the world to establish." (Quoted in Introduction to Astronomy by F. R. Mouton)

Ernst Mach:
"...the language of everyday life has not yet grown to be sufficiently accurate for the purposes so exact a science as mechanics." (Preface to The Science of Mechanics by Thomas McCormack)

James Clerk Maxwell:
"In applying dynamical principles to the motion of immense numbers of atoms, the limitation of our faculties forces us to abandon the attempt to express the exact history of each atom, and to be content with estimating the average condition of a group of atoms large enough to be visible. This method... which I may call the statistical method, and which in the present stage of knowledge is the only available method of studying the properties of real bodies, involves an abandonment of strict dynamical principles, and an adoption of the mathematical methods belonging to the theory of probability." (Introductory Lecture on Experimental Physics, 1890)

Dmitri Mendeleev:
"I suppose when my unknown elements are found, more people will pay us attention." (An Outline of the System of Elements)

Dmitri Mendeleev:
"We should still expect to discover many unknown simple bodies; for example, those similar to aluminum and silicon, elements with atomic weights of 65 to 75." (An Outline of the System of Elements)

Dmitri Mendeleev:
"The elements which are the most widely diffused have small atomic weights." (AZquotes.com)

Dmitri Mendeleev:
"The magnitude of the atomic weight determines the character of the element, just as the magnitude determines the character of a compound body." (Brainyquote.com)

Dmitri Mendeleev:
"We could live at the present day without a Plato, but a double number of Newtons is required to discover the secrets of nature, and to bring life into harmony with the laws of nature." (Brainyquote.com)

Augustus De Morgan:
"During the last two centuries and a half, physical knowledge has been gradually made to rest upon a basis which it had not before. It has become mathematical." (A Budget of Paradoxes, 1872)

Philip Morrison:
"I live next to the chemists at MIT, but I never see them. I hardly know who they are, yet between physics and chemistry it is hard to know who should study what molecule." (Nothing is Too Wonderful to be True, 1995)

John Polkinghorne:
"Quantum theory also tells us that the world is not simply objective; somehow its something more subtle than that. In some sense it is veiled from us, but it has a structure that we can understand." (Divine Action: interview with Lyndon Harris)

Hilary Putnam:
"The physicist who states a law of nature with the aid of a mathematical formula is abstracting a real feature of a real material world, even if he has to speak of numbers, vectors, tensors, state functions, or whatever to make the abstraction." (What is Mathematics, 1979)

Bernhard Riemann:
"As is known, scientific physics dates its existence from the discovery of the differential calculus. Only when it was learned how to follow continuously the course of natural events, attempts, to construct by means of abstract conceptions the connection between phenomena, met with success." (Wikiquote)

Bertrand Russell:
"Ordinary language is totally unsuited for expressing what physics really asserts, since the words of everyday life are not sufficiently abstract. Only mathematics and mathematical logic can say as little as the physicist means to say." (The Scientific Outlook, 1931)

Bertrand Russell:
"Physics is mathematical not because we know so much about the physical world, but because we know so little: it is only its mathematical properties that we can discover." (An Outline of Philosophy, 1927)

Ernest Rutherford:
"I must confess it was it was very unexpected and I am very startled at my metamorphosis into a chemist." (Quoted in Nobel Laureates and 20th Century Physics by Mauro Dardo)

Ernest Rutherford:
"We're like children who always want to take apart watches to see how they work." (Quoted in Seeing the Unseen by Freeman Dyson)

Ernest Rutherford:
"When we have found how the nucleus of atoms is built up we shall have found the greatest secret of all - except life. We shall have found the basis of everything - of the earth we walk on, of the air we breathe, of the sunshine, of our physical body itself, of everything in the world, however great or however small - except life." (Quoted in The Wit and Wisdom of the 20th Century by Frank Pepper)

John of Salisbury:
"There thus developed two branches of philosophy, natural and moral, which are also called ethics and physics." (The Metalogicon of John of Salisbury, 1159)

William Thomson:
"If, then, the motion of every particle of matter in the universe were precisely reversed at any instant, the course of nature would be simply reversed forever after." (The Kinetic Theory of the Dissipation of Energy, 1874)

Hermann Weyl:
"Riemann... clearly left the real development of his ideas in the hands of some subsequent scientist whose genius as a physicist could rise to equal flights with his own as a mathematician. After a lapse of 70 years this mission has been fulfilled by Einstein." (Space-Time-Matter, 1952)

Hermann Weyl:
"A new development began for relativity theory after 1925 with its absorption into quantum physics. The first great success was scored by Dirac's quantum mechanical equations of the electron, which introduced a new sort of quantities, the spinors, besides the vectors and tenors into our physical theories." (Space-Time-Matter, 1952)

William Whewell:
"Such a mode of discussion as this, led to no [physical] truths of real or permanent value. The whole mass of Greek philosophy... shrinks into an almost imperceptible compass, when viewed with reference to the progress of physical knowledge." (History of the Inductive Sciences, 1837)

Eugene Wigner:
"The miracle of the appropriateness of the language of mathematics for the formulation of the laws of physics is a wonderful gift which we neither understand nor deserve." (The Unreasonable Effectiveness of Mathematics in the Natural Sciences, 1960)

Edward Witten:
"It is very possible that a proper understanding of string theory will make the space-time continuum melt away... string theory is a miracle through and through." (Quoted in A Theory of Everything by K. C. Cole)

Edward Witten:
"Vibrating strings in 10 dimensions is just a a weird fact... an explanation of that weird fact would tell you shy there are 10 dimensions in the first place." (Quoted in A Theory of Everything by K. C. Cole)

Edward Witten:
"The essence of it is that physics is about concepts, wanting to understand the concepts, the principles by which the world works." (Interview with Davies and Brown, 1992)

Edward Witten:
"In Newton's day the problem was to write somethign which was correct - he never had the problem of writing nonsense, but by the 20th century we have a rich conceptual framework with relativity and quantum mechanics and so on. In this framework its difficult to do things which are even internally correct, much less correct. Actually, that's fortunate int he sense that it's one of the main tools we have in trying to make progress in physics." (Interview with Davies and Brown, 1992)

Edward Witten:
"String theory at its finest is, or should be, a new branch of geometry... I, myself, believe rather strongly that the proper setting for string theory will prove to be a suitable elaboration of the geometrical ideas upon which Einstein based General Relativity." (Interview with Davies and Brown, 1992)

Edward Witten:
"I would expect that a proper elucidation of what string theory really is all about would involve a revolution in our concepts of the basic laws of physics - similar in scope to any that occurred in the past." (Interview with Davies and Brown, 1992)

Edward Witten:
"Generally speaking, all the really great ideas of physics are really spin-offs of string theory... some of them were discovered first, but I consider that a mere accident of the development of planet Earth." (Quoted in The End of Science by John Horgan)

Edward Witten:
"As of now, string theorists have no explanation of why there are three large dimensions as well as time, and the other dimensions are are microscopic. Proposals about that have been all over the map." (Brainyquote.com)

Edward Witten:
"If I take the theory as we have it now, literally, I would conclude that extra dimensions really exist. They're part of nature. We don't know how big they are yet, but we hope to explore that in various ways." (Brainyquote.com)

Edward Witten:
"Spreading out the particle into a string is a step in the direction of making everything we're familiar with fuzzy. You enter a completely new world where things aren't at all what you're used to." (Brainyquote.com)

Edward Witten:
"String theory is an attempt at a deeper description of nature by thinking of an elementary particle not as a little point but as a little loop of vibrating string." (Goodreads.com)

40. Pictures

J. L. Austin:
"Going back into the history of a word, very often into Latin, we come back pretty commonly to pictures or models of how things happen or are done... but one of the commonest and most primitive types of model is one which is apt to baffle us through its very naturalness and simplicity." (A Plea for Excuses, 1956)

Lancelot Hogben:
"In communicating information about different sorts of things in the world, primitive man first learned to substitute crude pictures for speech to record seasonal occurrence for future use... As time went on the pictorial character of writing became less recognizable." (Mathematics for the Million, 1936)

Robert Andrew Wilson, Frank Keil:
"However, the central role of imagery in theories of mental activity was undermined when Kulpe, in 1904, pointed out that some thoughts are not accompanied by imagery..." (The MIT Encyclopedia of Cognitive Sciences, 2001)

41. Probability

Claude Bernard:
"A great surgeon performs operations for stone by a single method; later he makes a statistical summary of deaths and recoveries, and he concludes from these statistics that the mortality law for this operation is two out of five. Well, I say that this ratio means literally nothing scientifically and gives us no certainty in performing the next operation; for we do not know whether the next case will be among the recoveries or the deaths. What really should be done, instead of gathering facts empirically, is to study them more accurately, each in its special determinism… to discover in them the cause of mortal accidents so as to master the cause and avoid the accidents." (Introduction à l'Étude de la Médecine Expérimentale, 1865)

Jacob Bernoulli:
"The art of measuring, as precisely as possible, probabilities of things, with the goal that we would be able to always to choose or follow in our judgments and actions that course, which will have been determined to be better, more satisfactory, safer, or more advantageous." (Ars Conjectandi, 1713)

Rene Descartes:
"It is a truth very certain that, when it is not our power to determine what is true, we ought to follow what is most probable." (Quoted in Control of Engineering by S. H. Wearne, 1989)

Bruno de Finetti:
"My thesis, paradoxically, and a little provactively, but nonetheless genuinely, is simply this: probability does not exist... Probability, too, if regarded as something endowed with some kind of objective existence, is no less a misleading misconception, an illusory attempt to exteriorize or materialize our true probabilistic beliefs." (Theory of Probability, 1970)

Ian Hacking:
"Opinion is the companion of probability within the medieval epistemology." (The Emergence of Probability, 1975)

Ian Hacking:
"Probability fractions arise from our knowledge and from our ignorance." (The Emergence of Probability, 1975)

David Hume:
"By this means all knowledge degenerates into probability; and this probability is greater or less, according to our experience of the veracity or deceitfulness of our understanding, and according to the simplicity or intricacy of the question." (A Treatise  of Human Nature, 1739)

Andrey Kolmogorov:
"The epistemological value of probability theory is based on the fact that chance phenomena, considered collectively and on a grand scale, create non-random regularity." (Limit Distributions for Sums of Independent Random Variables, 1954)

Pierre-Simon Laplace:
"One sees, from this essay, that the theory of probabilities is basically just common sense reduced to calculus; it makes one appreciate with exactness that which accurate minds feel with a sort of instinct, often being able to account for it." (Theorie Analytique des Probabilities, 1814)

Pierre-Simon Laplace:
"Life's most important questions are, for the most part, nothing but probability problems." (Wikiquote)

Pierre-Simon Laplace:
"The theory of chance consists in reducing all events of the same kind to a certain number of cases equally possible." (Philosophical Essays on Probabilities, 1812)

Dennis Lindley:
"It's not merely a question of calculating with probabilities but also one of relating the ingredients of your probability statements to reality. You do not need to think only about P(E|K) but also about the precise nature of E and K." (Understanding Uncertainty, 2006)

Richard von Mises:
"The theory of probability can never lead to a definite statement concerning a single event." (Probability, Statistics and Truth, 1957)

Richard von Mises:
"Mass phenomena to which the theory of probability does not apply are, of course, of common occurrence." (Probability, Statistics and Truth, 1957)

Richard von Mises:
"If the concept of probability and the formulae of the theory of probability are used without clear understanding of the collectives involved, one may arrive at entirely misleading results." (Probability, Statistics and Truth, 1957)

Richard von Mises:
"In games of chance, in the problems of insurance, and in the molecular processes we find events repeating themselves again and again." (Probability, Statistics and Truth, 1928)

Richard von Mises:
"It has been asserted - and this is not overstatement - that whereas other sciences draw their conclusions from what we know, the science of probability derives its most important results form what we don't know." (Probability, Statistics and Truth, 1928)

John von Neumann:
"For, as has been pointed out several times, there is no such thing as a random number - there are only methods to produce random numbers, and a strict arithmetic procedure of course in not such a method." (Monte Carlo Method, 1951)

Fredrik Pollock:
"Circumstantial evidence only raises a probability." (Reg. v. Rowton, 1865)

Aldolphe Quetelet:
"It has seemed to me that the theory (calcul) of probabilities ought to serve as the basis for the study of all the sciences, and particularly of the sciences of observation." (Instructions Populaires sur le Calcul des Probability, 1825)

Erwin Schrodinger:
"God knows I am no friend of probability theory, I have hated it from the first moment when our dear friend Max Born gave it birth. For it could be seen how easy and simple it made everything, in principle, everything ironed and the true problems concealed." (Letter to Albert Einstein, 1946)

Noah Smith:
"Significance tests results shouldn't be used in a vacuum - to do good science, you should also look at effect sizes and goodness-of-fit." (The backlash to the backlash against p-values, 2015)

Noah Smith:
"What is a probability in the first place? I mean, sure, it's a number between 0 and 1 that you assign to events in a probability space. But how should we use that mathematical concept to represent events in the real world? What observable things should we represent with those numbers, and how should we assign the numbers to the things?" (I still don't understand the philosophy of Bayesian probability, 2014)

42. Questions

Roger Bacon:
"To ask the proper question is half of knowing." (Quoted in Life, Sept 8, 1958)

Jacques Bertin:
"There are as many types of questions as components in the information." (Semiotics of Graphics, 1967)

Enrico Bombieri:
"When things get too complicated, it sometimes makes sense to stop and wonder: have I asked the right question?" (Quoted in The Myth of Executive functioning by Leonard Koziol)

Giannina Braschi:
"Questions don't change the truth but they give it motion." (Empire of Dreams, 1988)

Georg Cantor:
"In mathematics, the art of asking questions is more valuable than solving problems." (Doctoral Thesis, 1867)

Georges Cuvier:
"It is evident that one cannot say anything demonstrable about the problem before having resolved these preliminary questions, and yet we hardly possess the necessary information to solve some of them." (1796, stated before the National Institute of Sciences and Arts in Paris)

Theodosius Dobzhansky:
"Any competent biologist is aware of a multitude of problems yet unresolved and of questions yet unanswered. After all, biological research shows no sign of approaching completion; quite the opposite is true." (Nothing in Biology Makes Sense Except in Light of Evolution, 1973)

Northrop Frye:
"The kind of problem that literature raises is not the kind that you ever 'solve'. Whether my answers are good or not, they represent a fair amount of thinking about the questions." (The Educated Imagination, 1963)

Indira Gandhi:
"The power to question is the basis of all human progress." (Misbehave: Speak Truth to Power, 2011)

David Hilbert:
"As long as a branch of science offers an abundance of problems, so long it is alive; a lack of problems foreshadows extinction or the cessation of independent development." (AZquotes.com)

David Hilbert:
"If I were to awaken after having slept for a thousand years, my first question would be: has the the Riemann hypothesis been proven?" (Quoted in Mathematical Mysteries by Calvin Clawson)

Eugene Ionesco:
"It is not the answer that enlightens but the question." (Quoted in 78 Important Questions Every Leader Should Ask and Answer, 2002)

Immanuel Kant:
"Human reason has this peculiar fate that in one species of its knowledge it is burdened by questions which, as prescribed by the very nature of reason itself, it is not able to ignore, but which, as transcending all its powers, it is also not able to answer." (Critique of Pure Reason, 1781)

Friedrich Nietzsche:
"But to stand in the midst of the midst of rerum concordia discors and this whole marvelous uncertainty and rich ambiguity in existence without questioning, without trembling with the craving and the rapture of such questioning..." (The Gay Science, 1882)

Linus Pauling:
"I have a great curiosity about the nature of the world as a whole, and most of my ideas are qualitative rather than quantitative." (Interview with George B. Kauffman and Laurie M. Kauffman, 1994)

Karl Popper:
"The more we learn about the world and the deeper our learning, the more conscious, specific and articulate will be our knowledge of what we do not know our knowledge of our ignorance." (Conjectures and Refutations: The Growth of Scientific Knowledge, 1963)

Bertrand Russell:
"I do not pretend to start with precise questions. I do not think you can start with anything precise. You have to achieve such precision as you can, as you go along." (The Philosophy of Logical Atomism, 1918)

Robert Schuller:
"Here's how to look at problems: problems are guidelines, not stop signs!" (Move Ahead with Possibility Thinking, 1967)

Ludwig Wittgenstein:
"Philosophical problems can be compared to locks on safes, which can be open by dialing a certain word or number so that no force can open the door until just this word has been hit upon, and once it is hit upon any child can open it." (Philosophical Occasions, 1993 posthumous)

43. Quotation

Marlene Dietrich:
"I love quotations because it is a joy to find thoughts one might have beautifully expressed with much authority by someone recognizably wiser than oneself." (Quoted in Presidential Wit and Wisdom by Brallier and Chabert)

Margaret Drabble:
"Sometimes it seems the only accomplishment my education ever bestowed on me, the ability to think in quotations." (A Summer Bird Cage, 1963)

Michel de Montaigne:
"I do not speak the minds of others except to speak my own mind better." (Essays 1922)

Marianne Moore:
"I've always felt that if a thing had been said the best way, how can you say it better?" (Paris Review interview, 1960)

Willis Regier:
"Quotation might 'appear trivial' yet also be 'an easy entrance to the labyrinth' of other heady problems: propositional attitudes, explicit performances and picture theories of reference." (Quotology, 2010)

44. Reason

Andre Marie Amphere
"There is synthesis when, in combing therein judgments that are made known to us from simpler relations, one deduces judgments from the relative to more complicated relations. There is analysis when from a complicated truth one deduces more simple truths." (Quoted in Andre-Marie Amphere: Enlightenment and Electrodynamics)

Archimedes:
"Those who claim to discover everything but produce not proofs of the same may be confuted as having actually pretended to discover the impossible." (On Spirals, 225 BC)

Aristotle:
"Knowledge of the fact differs from knowledge of the reason for the fact." (Posterior Analytics)

Aristotle:
"Universal is know according to reason, but that which is particular according to sense." (Physics)

Aristotle:
"The natural way of doing this (seeking scientific knowledge or explanation of fact) is to start from the things which are more knowable and obvious to us and proceed towards those which are clearer and more knowable by nature; for the same things are not 'knowable relatively to us' and 'knowable' without qualification. So in the present inquiry we must follow this method and advance from what is more obscure by nature, but clearer to us, towards what is more clear and more knowable by nature. Now what is to us plain and obvious at first is rather confused masses, the elements and principles of which became known to us by later analysis." (Physics)

Isaac Asimov:
"I believe in evidence. I believe in observation, measurement and reasoning confirmed by independent observers." (The Roving Mind)

Francis Bacon:
"Those who have handled sciences have been either men of experiment or men of dogmas. The men of experiment are like the ant, they only collect and use; the reasoners resemble spiders, who make cobwebs out of their own substance. But the bee takes a middle course: it gathers its material from the flowers of the garden and of the field, but transforms and digests it by a power of its own. " (Novum Organum, 1620)

Roger Bacon:
"Reasoning draws a conclusion and makes us grant the conclusion, but does not make the conclusion certain, nor does it remove doubt so that the mind may rest on the intuition of truth, unless the mind discovers it by the path of experience." (1267, Opus Majus)

George Boole:
"[My goal is to] unfold the secret laws and relations of those high faculties of though by which all beyond the merely perceptive knowledge of the world and of ourselves is attained or matured, is a object which does not stand in need of commendation to a rational mind." (An Investigation into the Laws of Thought, 1854)

Max Born:
"...reason distinguishes between the sensible and the senseless." (The Voyage into the Dark, 1961

Edwin Arthur Burtt:
"The central place of epistemology in modern philosophy is no accident." (The Metaphysical Foundations of Modern Physical Science, 1925)

Fausto Cercignani:
"Even good arguments fail, if they are spiced with digressions." (Quoted in Quotations from Fausto Cercignani by Brian Morris, 2014)

Luc de Clapiers, Marquis de Vauvenargues:
"Reason deceives us more often than nature." (Reflections and Maxims, 1746)

Paul Cohen:
"However, in all honesty, I must say that one must essentially forget that all proofs are transcribed in this formal language. In order to think productively, one must use all the intuitive and informal methods of reasoning at one's disposal. At the very end one must check that no errors have been committed..." (The Discover of Forcing, 2002)

Etienne Bonnet de Condillac;
"We think only through the medium of words. Languages are true analytical methods. Algebra, which is adapted to its purpose in every species of expression, in the most simple, most exact, and best manner possible, is at the same time a language and an analytical methods. The art of reasoning is nothing more than a language well arranged." (Quoted in A System of Logic by Antoine Lavoisier)

Gilles Deleuze:
"Evaluations, in essence, are... ways of being, modes of existence of those who judge and evaluate." (Nietzsche and Philosophy, 1962)

Giles Deleuze:
"It is not the slumber of reason that engenders monsters, but vigilant and insomniac rationality." (Anti-Oedipus: Capitalism and Schizophrenia, 1972)

Giles Deleuze:
"Underneath all reason lies delirium and drift." (AZquotes.com)

Rene Descartes:
"The aim of our studies must be the direction of our mind so that it may form solid and true judgments on whatever matters arise." (Rules for the Direction of the Mind, 1628)

Rene Descartes:

"No more useful inquiry can be proposed than that which seeks to determine the nature and the scope of human knowledge." (Rules for the Direction of the Mind, 1628)

John Dewey:
"Human reason, all too human, have given birth to the idea that over and beyond the lower realm of things that shift like the sands on the seashore there is the kingdom of the unchanging, of the complete the perfect... the eternal and immutable is the consummation of mortal man's quest for certainty." (Time and Individuality, 1940)

Albert Einstein:
"When I think about the ablest students whom I have encountered in my teaching, that is, those who distinguish themselves by their independence of judgement and not merely their quick wittedness, I can affirm that they had a vigorous interest in epistemology." (Physikalische Zeitschrift, 1916)

L. C. J. Eyre:
"It is difficult to say what is or is not evidence itself, because it all depends upon the chain and connection it has - if there are two or three links in the chain, they must go to one first and then to another, and see whether they amount to evidence." (Tooke's Case. 1794)

Michel Foucault:
"If our intention now is to reveal classical unreason on its own terms, outside of its ties with dreams and error, it must be understood not as a form of reason that is somehow diseased lost or mad, but quite simply as reason dazzled." (History of Madness, 1961)

Johann Georg Harmann:
"Reason is language - logos." (Breifwechsel, 1955)

William Harvey:
"The studious and good and true, never suffer their minds to be warped by the passions of hatred and envy, which unfit men duly to weigh the arguments that are advanced in behalf of truth, or to appreciate the proposition that is even fairly demonstrated." (Dedication of Dr. Argent and Other Learned Physicians)

Sherlock Holmes:
"How often have I said to you that when you have eliminated the impossible, whatever remains, however improbable, must be the truth?" (In Arthur Conan Doyle's Sign of the Four Chap)

David Hume:
"There is nothing in any object, considered in itself, which can afford us a reason for drawing a conclusion beyond it... even after the observation of the frequent or constant conjunction of objects, we have no reason to draw any inference concerning any object beyond those of which we have had experience." (A Treatise  of Human Nature, 1739)

David Hume:
"Reason is nothing but a wonderful and intelligible instinct in our souls." (A Treatise  of Human Nature, 1739)

David Hume:
"In our reasonings concerning matter of fact, there are all imaginable degrees of assurance, from the highest certainty to the lowest species of moral evidence. A wise man, therefore proportions his beliefs to the evidence." (An Enquiry Concerning Human Understanding, 1748)

David Hume:
"I weigh the one miracle against the other; and according to the superiority, which I discover, I pronounce my decision and always reject the greater miracle." (An Enquiry Concerning Human Understanding, 1748)

Thomas Henry Huxley

"The method of scientific investigation is nothing but the expression of the necessary mode of working of the human mind." (Our Knowledge of the Causes of the Phenomena of Organic Nature, 1863)

Christian Huygens:
"There are many degrees of probable, some nearer truth than others, in the determining of which lies the chief exercise of our judgement." (Cosmotheoros, 1695)

Michael C. Jackson:
"The problem solver needs to stand back and examine problem contexts in the light of different W's (weltanschauungen). Perhaps they can decide which W seems to capture the essence of the particular problem context he is faced with." (Towards a System of Systems Methodologies, 1984)

William Stanley Jevons:
"I shall endeavor to show that induction is really the inverse process of deduction." (The Principles of Science, 1874)

Immanuel Kant:
"Reason in a creature is a faculty of widening the rules and purposes of all its powers far beyond natural instinct; it acknowledges no limits to its projects. Reason itself does not work instinctively, but requires trial, practice and instruction in order to gradually to progress from one level of insight to another." (Idea for a Universal History from a Cosmopolitan Point of View, 1784)

Immanuel Kant:
"I freely admit that the remembrance of David Hume was the very thing that many years ago first interrupted my dogmatic slumber and gave a completely different direction to my researches in the field of speculative philosophy." (Prolegomena to any Future Metaphysics, 1783)

Immanuel Kant:
"Mathematics, from the earliest times to which the history of human reason can reach, has followed, among that wonderful people of the Greeks, the safe way of science. But it must not be supposed that it was as easy for mathematics as for logic, in which reason is concerned with itself alone, to find, or rather to make for itself that royal road." (Critique of Pure Reason, 1781)

Thomas Kuhn:
"Only when they must choose between competing theories do scientists behave like philosophers." (1970, Logic of Discovery or Psychology of Research)

Tony Lawson:
"Most problem solving occurs on the job. We need to know the nature of the problem we're dealing with." (What's Wrong with Modern Economics? YouTube 2015)

Antoine Lavoisier:
"The art of concluding from experience and observation consists in evaluating probabilities, in estimating if they are high or numerous enough to constitute proof." (Rapport des commissaires charges par le roi de l'exemen du magnetism animal, 1784)

John Locke:
"For when all is done, this is the highest and most important faculty of our minds, deserves the greatest care and attention in cultivating it: the right improvement, and exercise of our reason being the highest perfection that a man can attain to in his life." (Some Thoughts Concerning Education, 1693)

Karl Mannheim:
"Conflicting intellectual positions may actually come to supplement one another." (Ideology and Utopia, 1929)

Karl Mannheim:
"As long as one does not call his own position into question but regards it as absolute, while interpreting his opponents' ideas as a mere function of the social positions they occupy, the decisive step forward has not yet been taken." (Ideology and Utopia, 1929)

Karl Mannheim:
"In attempting to expose the views of another, one is forced to make one's own view appear infallible and absolute, which is a procedure altogether to be avoided if one is making a specifically non-evaluative investigation." (Ideology and Utopia, 1929)

John Stuart Mill:
"He who knows only his own side of the case, knows little of that. His reasons may be good and no one may have been able to refute them. But if he is equally unable to refute the reasons on the opposite side; if he does not so much as know what they are, he has no ground for preferring either opinion." (Of Liberty, 1859)

John Stuart Mill:
"Since reasoning, or inference, the principal subject of logic, is an operation which usually takes place by means of words, and in complicated cases can take place in no other way: those who have not a thorough insight into both the signification and purpose of words, will be under chances, amounting almost to certainty, of reasoning or inferring incorrectly." (A System of Logic, 1843)

Marvin Minsky:
"I am inclined to doubt that anything very resembling formal logic could be a good model for human reasoning." (Jokes and their Relation to the Cognitive Unconscious, 1980)

G. E. Moore:
"I can prove now, for instance that two human hands exist. How? By holding up my two hands and saying, as I make a certain gesture with the right hand, 'here is one hand' and adding, as I make a certain gesture with the left, 'and here is the another'. And if by going this, I have proved ipso facto the existence of external things, you will all see that I can also do it now in numbers of other ways: there is no need to multiply examples." (Proof of an external world, 1939)

G. E. Moore:
"For it is the business of Ethics, I must insist, not only to obtain true results, but also to find valid reasons for them." (Principia Ethica, 1903)

Emmy Noether:
"My methods are really methods of working and thinking; this is why they have crept in everywhere anonymously." (Letter to Helmut Hasse, 1931)

William of Ockham:
"You see that I have set out opposing assertions in response to your question and I have touched on quite strong arguments in support of each position. Therefore consider now which seems the more probable to you." (Dialogus, 1494)

William of Ockham:
"For nothing ought to be posited without a reason given, unless it is self-evident (literally known through itself) or known by experience or proved by the authority of Sacred Scripture." (AZQuotes.com)

Linus Pauling:
"Facts are the air of scientists. Without them you can never fly." (Brainy Quote)

Benjamin Peirce:
"Symbols are essential to comprehensive argument." (On the Uses and Transformations of Linear Algebra, 1875)

Charles Sanders Peirce:
"An 'argument' is any process of thought reasonably trending to produce a definite belief. An 'argumentation' is an argument proceeding upon definitely formulated premises." (A Neglected Argument for the Reality of God, 1908)

Jordan Peterson:
"That's a way that you can tell if you got an argument right: it's communicable, understandable and memorable." (Wikiquote)

Karl Popper:
"He is well aware that acceptance or rejection of an idea is never a purely rational matter; but he thinks that only critical discussion can give us the maturity to see an idea from more and more sides and to make a correct judgement of it." (All Life is Problem Solving, 1997)

Pythagoras:
"Reason is immortal, all else mortal." (Quoted in Lives and Opinions of Eminent Philosophers by Diogenes Laertius)

Pythagoras:
"The soul of man is divided into three parts: intelligence, reason and passion. Intelligence and passion are possessed by other animals, but reason by man alone." (Quoted in Lives and Opinions of Eminent Philosophers by Diogenes Laertius)

Pythagoras:
"The oldest, shortest words - 'yes' and 'no' - are those which require the most thought." (Quoted in Numerology for Relationships: A Guide to Birth Numbers by Vera Kaikobad)

Bertrand Russell:
"A hallucination is a fact, not an error; what is erroneous is a judgement based upon it." (On the Nature of Acquaintance, 1914)

Bertrand Russell:
"I may as well say at once that I do not distinguish between inference and deduction. What is called induction appears to me to be either disguised deduction or a mere method of making plausible guesses." (Principles of Mathematics, 1903)

Bertrand  Russell:
"When you are studying any matter, or considering any philosophy, ask yourself only: what are the facts and what is the truth the facts bear out?" (BBC interview, 1959)

Arthur Schopenhauer:

"Every true thinker for himself is so far like a monarch; he is absolute, and recognizes nobody above him. His judgments, like the decrees of a monarch, spring from his own sovereign power and proceed directly from himself. He takes as little notice of authority as a monarch does of a command; nothing is valid unless he has himself authorized it." (Parerga and Paralipomena, 1851)

Noah Smith:
"If an expert or guru can't point to some research that supports his pronouncements, you shouldn't trust that his brain just works better than yours." (Beware of thinking like an economist, 2017)

Gertrude Stein:
"Argument is to me the air I breathe. Given any proposition, I cannot help believing the other side and defending it." (Form and Intelligibility, 1949)

Voltaire:
"A witty saying proves nothing." (Le diner du comte de Boulainvilliers, 1767)

Isaac Watts:
"Synthetic method is that which begins with parts and leads onward to the knowledge of the whole: it begins with the most simple principles and general truths and proceeds by degrees to that which is drawn from them, or compounded of them; and therefore it is called the method of composition." (Quoted in Prose Quotations from Socrates to Macaulay by Austin Allibone)

Simone Weil:
"The most important part of education - to teach the meaning of to know." (Waiting on God, 1950 posthumous)

Richard Whatley:
"The easiest and most popular way of practically refuting... any fallacy is, by bringing forward a parallel case, where it leads to a manifest absurdity." (Elements of rhetoric, 1828)

Alfred North Whitehead:
"Rationalism is an adventure in the clarification of thought." (Process and reality: An essay in cosmology, 1929)

Alfred North Whitehead:
"The chief danger to philosophy is narrowness in the selection of evidence." (Process and reality: An Essay in Cosmology, 1929)

Alfred North Whitehead:
"Some philosophers fail to distinguish propositions from judgments... But in the real world it is more important that a proposition be interesting than that it be true. The importance of truth is that it adds to interest." (Process and Reality: An Essay in Cosmology, 1929)

Alfred North Whitehead:
"The main importance of Francis Bacon's influence does not lie in any peculiar theory of inductive reasoning which he happened to express, but in the revolt against second-hand information of which he was a leader." (The Aims of Education, 1929)

Francis Wright:
"All that I say is, examine. Look into the nature of things. Search out the grounds of your opinions, the for and the against. Know why you believe, understand what you believe and possess a reason for the faith that is in you..." (A Course of Popular Lectures, 1829)

Muhammad Ibn Zakariya:
"If they consider my approach incorrect they could present their views and state their points clearly, so that I may study them, and if I determined their views to be right, I would admit it. However if I disagreed I would discuss the matter to prove my standpoint." (Quoted in The Lost History: The Enduring Legacy of Muslim Scientists, Thinkers and Artists)

45. Reductionism

Alberto-Laszlo Barabasi:
"Reports of the death of reductionism are greatly exaggerated. It is so ingrained in our thinking that if one day some magical force should make us forget it, we would promptly have to reinvent it." (The Network Takeover, 2012)

Robert Boyle:
"I consider then, that generally speaking, to render a reason of an effect or phaenomenon, is to deduce it from something else in nature more known than itself, and that consequently there may be divers kinds of degrees of explication of the same thing." (Physiological Essays, 1669)

Rene Descartes:
"Divide each difficulty into as many parts as is feasible and necessary to resolve it." (Le Discours de la Methode, 1637)

David Hume:
"Look round the world: contemplate the whole and every part of it: you will find it to be nothing but one great machine, subdivided into an infinite number of lesser machines, which again admit of subdivisions, to a degree beyond what human senses and faculties can trace and explain." (Dialogues Concerning Natural Religion, 1779)

David Hume:
"Did I show you the particular cause of each individual in a collection of 20 particles of matter I should think it very unreasonable, should afterwards ask me, what was the cause of the whole 20. This is sufficiently explained in explaining the cause of the parts." (Dialogues Concerning Natural Religion, 1779)

Michael C. Jackson:
"Reductionism sees the parts as paramount and seeks to identify the parts, understand the parts to an understanding of the whole. The problem with this is that the whole often seems to take on a form that is not recognizable from its part." (Systems Thinking: Creative holism for managers, 2003)

Michael C. Jackson:
"The classification of a system as complex or simple will depend upon the observer of the system and upon the purpose they have for considering the system." (Towards a System of Systems Methodologies, 1984)

Gottfried Wilhelm Leibniz:
"...I hold that all things take place mechanically as Democritus and Descartes contend against the views of Henry More and his followers, and hold too, nevertheless, that everything takes place according to a living principles and according to final causes..." (Letter to Thomas Burnet, 1697)

Mikhail Lomonosov:
"Nature uncovers the inner secrets of nature in two ways: one by the force of bodies operating outside it; the other by the very movements of its innards. The external actions are strong winds, rains, river currents, sea waves, ice, forest fires, floods; there is only one internal force-earthquake." (AZ Quotes)

William Poundstone:
"Reductionism will not be truly successful until physicists and cosmologists demonstrate that the large-scale phenomena of the world arise for fundamental physics along. This lofty goal is still out of reach." (The Recursive Universe, 1985)

46. Relativism

Dinesh D'Souza:
"Strictly speaking, relativism does not permit social progress, because the new culture is by definition no better than the one it replaced." (The End of Racism, 1995)

Jerry Fodor:
"I hate relativism. I hate relativism more than I hate anything else, except maybe, fiberglass powerboats... Surely, surely, no one but a relativist would drive a fiberglass powerboat." (The Modularity of Mind, 1985)

Ian Hacking:
"There's a long and complicated story of the rise of a desire for scientific relativism. Part of it may well be simply sort of rage against reason, the fear of the sciences and a kind of total dislike of the arrogance of a great many scientists who say we're find out the truth about everything..." (Q & A with Ian Hacking on Thomas Kuhn's Legacy, 2012)

Ian Hacking:
"Some of that work, with its emphasis on the idea that facts are 'socially constructed' and apparent participation in the denial of 'truth' is exactly what conservative scientists protested against. Kuhn made plain that he himself detested that development of his work." (Introductory Essay to The Structure of Scientific Revolution by Thomas Kuhn)

47. Rhetoric

Stephen Cobert:
"Language has always been important in politics, but language is incredibly important to the present political struggle." (Interview with New York Magazine, 2006)

Albert Einstein:
"Clarity about the aims and problems of socialism is of the greatest significance in our age of transition." (Einstein on Politics: His Private Thoughts and Public Stands on Nationalism)

Leon Festinger:
"When there is a range of opinion in the group, communications tend to be directed towards those members whose opinions are at the extremes of the range." (Interpersonal Communication in Small Groups, 1951)

Jane Goodall:
"Especially now when views are becoming more polarized, we must work to understand each other across political, religious and national boundaries." (Quoted in Verge Magazine, 2010)

John Maynard Keynes:
"Words ought to be a little wild, for they are the assault of thoughts on the unthinking." (New Statesman and the nation, 1933)

Blaise Pascal:
"Of the truths within our reach... the mind and the heart are as doors by which they are received into the soul, but... few enter by the mind, whilst they are brought in crowds by the rash caprices of the will, without the council of reason." (The Art of Persuasion)

Blaise Pascal:
"It is necessary to have regard to the person whom we wish to persuade, of whom we must know the mind and the heart, what principles he acknowledges, what things he loves; and then observe in the thing in question what affinity it has with the acknowledged principles, or with the objects so delightful by the pleasure which they give him." (The Art of Persuasion)

Plato:
"Rhetoric, it seems, is a producer of persuasion for belief, not for instruction in the matter of right and wrong … And so the rhetorician's business is not to instruct a law court or a public meeting in matters of right and wrong, but only to make them believe." (Wikiquote)

I. A. Richards:
"Rhetoric, I shall urge, should be a study of misunderstanding and it's remedies." (Philosophy of Rhetoric, 1964)

Jean-Paul Sartre:
"Politics is science. You can demonstrate that you are right and that others are wrong/" (Dirty Hands, 1948)

Baruch Spinoza:
"Ignorance is no argument." (Ethica Ordine Geomertrico Demonstrata et in Quinque Parses Distincta, 1677)

48. Sense

Francis Bacon:
"Now my method, though hard to practice is easy to explain; and it is this. I propose to establish progressive stages of certainty. The evidence of the sense, helped and guarded by a certain process of correction, I retain. But the mental operation which follows the act of sense I for the most part reject; and instead of it I open and lay out a new and certain path for the mind to proceed in, starting directly from the simple sensuous perception." (Novum Organum, 1620)

Francis Bacon:
"The human understanding is like a false mirror, which, receiving rays irregularly, distorts and discolors the nature of things by mingling its own nature with it." (Novum Organum, 1620)

Francis Bacon:
"Man, being the servant and interpreter of nature, can do and understand so much only as he has observed in fact or thought of the course of nature. Beyond this he neither knows anything nor can do anything." (Novum Organum, 1620)

Francis Bacon:
"There are and can be only two ways of searching into and discovering truth. The one flies from the sense and particulars to the most general axioms, and from these principles the truth of which it takes for settled and immovable, proceeds to judgement and to the discovery of middle axioms. And this way is now in fashion. The other derives axioms from the sense and particulars, rising by a gradual and unbroken ascent, so that it arrives at the most general axioms last of all. This is the true way, but as of yet untried." (Novum Organum, 1620)

Jean Baudrillard:
"Information can tell us everything. It has all the answers to questions we have not asked and which doubtless don't even arise." (Cool Memories, 1987)

Daniel Boorstin:
"While knowledge is orderly and cumulative, information is random and miscellaneous." (Gresham's Law: Knowledge or Information, 1989)

Democritus:
"We know nothing accurately in reality, but [only] as it changes according to the bodily condition, and the constitution of those things that flow upon [the body] and impinge upon it." (Wikiquote)

Epicurus:
"We must consider both the ultimate end and all clear sensory evidence, to which we refer our opinions; for otherwise everything will be full of uncertainty and confusion." (Sovereign Maxims)

Northrop Frye:
"There is a curious law of art... that even the attempt to reproduce the act of seeing, when carried out with sufficient energy, tends to lose its realism and take on the unnatural glittering intensity of hallucination." (The Critical Path and Other Writings on Critical Theory, 1962-1975)

William Harvey:
"When in many dissections, carried out as opportunity offered upon living animals, I first addressed my mind to seeing how I could discover the function and offices of the heart's movement in animals through the use of my own eyes instead of through the books and writings of others." (De Motu Cordis, 1628)

William Harvey:
"I profess both to learn and to teach anatomy not from books but from dissections; not from positions of philosophers but from the fabric of nature." (Dedication of Dr. Argent and Other Learned Physicians)

William Harvey:
"There is no science which does not spring from pre-existing knowledge, and no certain and definite idea which has not derived its origin from the senses." (Quoted in The First Anatomical Disquisition on the Circulation of the Blood by Willis and Bowie)

Robert Hooke:
"The truth is, the Science of Nature has been already too long made only a work of the Brain and the Fancy: It is now high time that it should return to the plainness and soundness of Observations on material and obvious things." (AZ Quotes)

David Hume:
"I never can catch myself at anytime without a perception, and never can observe anything but the perception." (A Treatise  of Human Nature, 1739)

Edmund Husserl:
"A new fundamental science, pure phenomenology, has developed within philosophy: this is a science of a thoroughly new type and endless scope. It is inferior in methodological rigor to none of the modern sciences. All philosophical disciplines are rooted in pure phenomenology..." (Pure Phenomenology, 1917)

Edmund Husserl:
"This concept of the phenomenon, which was developed under various names as early as the 18th century without being clarified, is what we shall have to deal with first of all." (Brainyquote.com)

Edmund Husserl:
"Within this widest concept of object, and specifically within the concept of individual object, objects and phenomena stand in contrast with each other." (Brainyquote.com)

William Stanley Jevons:
"In a certain sense all knowledge is inductive. We can only learn the laws and relations of things in nature by observing those things." (The Principles of Science, 1874)

Mary Leakey:
"Theories come and go, but fundamental data always remain the same." (Brainy Quote)

John Locke:
"No man's knowledge here can go beyond his experience." (An Essay Concerning Human Understanding, 1689)

Immanuel Kant:
"That all our knowledge begins with experience there can be no doubt. For how is it possible that the faculty of cognition should be awakened into exercise otherwise than by means of object which affect our senses and partly of themselves produce representations, partly rouse our powers of understanding into activity, to compare, to connect, or to separate these, and so to convert the raw material of our sensuous impressions into a knowledge of objects, which is call experience?" (Critique of Pure Reason, 1781)

Immanuel Kant:
"It is therefore, a question which requires close investigation, and its not to be answered at first sight - whether there exists a knowledge altogether independent of experience, and even of all sensuous impressions? Knowledge of this is called a priori. In contradistinction to empirical knowledge which has its sources a posteriori, that is, in experience." (Critique of Pure Reason, 1781)

Immanuel Kant:
"All our knowledge falls with the bounds of experience." (Critique of Pure Reason, 1781)

Lucretius:
"What can give us more sure knowledge than our senses? How else can we distinguish between true and the false?" (De Rerum Natura)

David Marr:
"Vision is a process that produces from images of the external world a description that is useful to the viewer and not cluttered with irrelevant information." (Representation and Recognition of the Spatial Organization of 3D Shapes, 1978)

Thomas Robert Malthus:
"The first business of philosophy is to account for things as they are; and till our theories will do this, they ought not to be the ground of any practical conclusion." (An Essay on the Principle of Population 2nd Edition, 1836)

John Stuart Mill:
"Whatever is known to us by consciousness, is known beyond possibility of question. What one sees or feels, whether bodily or mentally, one cannot but be sure that one sees or feels." (A System of Logic, 1843)

Friedrich Nietzsche:
"Between two absolutely different spheres, as between subject and object, there is no causality, no correctness and no expression; there is at most, an aesthetic relation." (On Truth and Lies in an Extra Moral Sense, 1873)

Robert Owen:
"Where are these rational practices to be taught and acquired? Not within the four walls of a bare building, in which formality predominates... But in the nursery, play-ground, fields, gardens, workshops, manufactures, museums and class-rooms." (The Book of the New Moral World, 1836)

Leonardo da Vinci:
"The eye, which is called the window of the soul, is the principal means by which the central sense can most completely and abundantly appreciate the infinite works of nature; and the ear is the second, which acquires dignity by hearing of the things the eye has seen." (Quoted by The Notebooks of Leonardo da Vinci by Rudolf Flesch)

Alfred Russel Wallace:
"When we touch matter, we only really experience sensations of resistance, implying repulsive force; and no other sense can give us such apparently solid proofs of the reality of matter, as touch does." (Considerations to the Theory of Natural Selection, 1870)

49. Skepticism

Alhazen:
"Thus the duty of the man who investigates the writings of scientists, if learning the truth is his goal, is to make himself an enemy of all that he reads, and applying his mind to the core and margins of its content, attack it from every side." (Quoted in Bridging Cultures Bookshelf: Muslim Journeys)

A. J. Ayer:
"There never comes a point where a theory can be said to be true. The most that one can claim for any theory is that it has shared the successes of all its rivals and that it has passed at least one test which they have failed." (Philosophy in the Twentieth Century, 1982)

Eric Temple Bell:
"Science makes no pretension to eternal truth or absolute truth; some of its rivals do." (Mathematics: Queen and Servant of Science, 1938)

George Berkeley:
"The same principles which at first view lead to skepticism, pursued to a certain point, bring men back to common sense." (Goodreads.com)

Rene Descartes:
"What is there, then, that can be esteemed true? Perhaps this only that there is absolutely nothing certain." (Meditations on First Philosophy, 1641)

Rene Descartes:
"We must occupy ourselves only with those objects that our intellectual powers appear competent to know certainly and indubitably." (Rules for the Direction of the Mind, 1628)

Rene Descartes:
"If you would be a real seeker after truth, you must at least once in your life doubt, as far as possible, all things." (Discours de la Methode)

Paul Feyerabend:
"Scientific 'facts' are taught at a very early age and in the very same manner in which religious 'facts' were taught only a century ago. There is no attempt to waken the critical abilities of the pupil so that he may see things in perspective. At the universities the situation is even worst..." (How To Defend Society Against Science, 1975)

Richard Feynman:
"A very great deal more truth can become known than can be proven." (Nobel Lecture: The Development of Space-Time View of Quantum Electrodynamics, 1965)

Stephen Hawking:

"Any physical theory is always provisional, in the sense that it is only a hypothesis: you can never prove it. No matter how many times the results of experiments agree with some theory, you can never be sure that the next time the result will not contradict the theory. On the other hand, you can disprove a theory by finding even a single observation that disagrees with the predictions of the theory." (A Brief History of Time, 1988)

Christian Huygens:
"I believe that we do not know anything for certain, but everything probably." (Letter to Pierre Perrault, 1673)

Immanuel Kant:
"It is precisely in knowing its limits that philosophy consists." (Critique of Pure Reason, 1781)

John Stuart Mill:
"As there were black swans, though civilized people have existed for three thousand years on the earth without meeting with them... The uniform experience, therefore, of the inhabitants of the known world, agreeing in a common result, without one known instance of deviation from that result, is not always sufficient to establish a general conclusion." (A System of Logic, 1843)

Plato:
"How can you prove whether at this moment we are sleeping, and all our thoughts are a dream; or whether we are awake, and talking to one another in the waking state?" (Brainyquote.com)

Karl Popper:
"...no matter how many instances of white swans we may have observed, this does not justify the conclusion that all swans are white." (The Logic of Scientific Discovery, 1934)

Bertrand Russell:
"To demand for certainty is one which is natural man, but is nevertheless an intellectual vice." (Philosophy of Laymen, 1946)

Carl Sagan:
"We have a method, and that method helps us to reach not absolute truth, only asymptotic approaches to the truth - never there, just closer and closer, always finding vast new oceans of undiscovered possibilities. Cleverly designed experiments are the key." (Wonder and Skepticism, 1995)

Carl Sagan:
"Science is... a way of skeptically interrogating the universe with a fine understanding of human fallibility. If we are not able to ask skeptical questions, to interrogate those who tell us that something is true, to be skeptical of those in authority, then we're up for grabs for the next charlatan, political or religious, who comes ambling along." (Interview with Charlie Rose, 1996)

Jean-Baptiste Say:
"A science only advances with certainty, when the plan of inquiry and the object of our researches have been clearly defined; otherwise a small number of truths are loosely laid hold of, without their connection being perceived, and numerous errors, without being enabled to detect their fallacy." (A Treatise On Political Economy 4th edition, 1832)

Socrates:
"I know nothing except just the fact of my ignorance." (Quoted by Diogenes Laertius)

Socrates:
"True wisdom comes to each of us when we realize how little we understand about life, ourselves, and the world around us." (Brainyquote.com)

Socrates:
"Smart people learn from everything and everyone, average people from their experiences, stupid people already have all the answers." (Goodreads.com)

Voltaire

"Doubt is not a pleasant condition, but certainty is an absurd one." (Letter to Frederick William, 1770)

50. Sociology and politics

Hannah Arendt:
"The trouble with Eichmann was precisely that so many were like him, and that the many were neither perverted nor sadistic, that they were, and still are, terribly and terrifyingly normal." (Eichmann in Jerusalem, 1963)

Hannah Arendt:
"The sad truth of the matter is that most evil is done by people who never made up their minds to be or do either evil or good." (The Life of the Mind, 1978 posthumous)

Hannah Arendt:
"So that instead of saying: 'What horrible things I did to people!' the murderers would be able to say: 'What horrible things I had to watch in the pursuance of my duties, how heavily the task weighed upon my shoulders!'" (Eichmann in Jerusalem, 1963)

Hannah Arendt:
"Totalitarianism begins in contempt for what you have. The second step is the notion: 'Things must change - no matter how. Anything is better than what we have.'" (Interview with Roger Errera, 1974)

Hannah Arendt:
"The moment we no longer have a free press, anything can happen. What makes it possible for a totalitarian or any other dictatorship to rule is that people not informed... If everybody always lies to you, the consequence is not that you believe the lies, but rather that nobody believes anything any longer." (Interview with Roger Errera, 1974)

Hannah Arendt:
"In an ever-changing, incomprehensible world the masses had reached the point where they would, at the same time, believe everything and nothing, think that everything was possible and that nothing was true... under such conditions, one could make people believe the most fantastic statements..." (The Origins of Totalitarianism, 1951)

Hannah Arendt:

"The totalitarian attempt at global conquest and total domination has been the destructive way out of all impasses. Its victory may coincide with the destruction of humanity; wherever it has ruled, it has begun to destroy the essence of man." (The Origins of Totalitarianism, 1951)

Simone de Beauvoir:
"...when we abolish the slavery of half of humanity, together with the whole system of hypocrisy that it implies then the 'division' of humanity will reveal its genuine significance and the human couple will find its true form." (The Second Sex, 1949)

Simone de Beauvoir:
"And yet we are told that femininity is in danger; we are exhorted to be women, remain women, become women. It would appear, then, that every female human being is not necessarily a woman; to be so considered she must share in that mysterious and threatened reality known as femininity." (The Second Sex, 1949)

Simone de Beauvoir:
"...the individual is defined only by his relationship to the world and to other individuals; he exists only by transcending himself, and his freedom can be achieved only through the freedom of others." (The Ethics of Ambiguity, 1947)

Noam Chomsky:
"Science talks about very simple things, and asks hard questions about them. As soon as things become too complex, science can't deal with them... But it's a complicated matter: Science studies what's at the edge of understanding, and what's at the edge of understanding is usually fairly simple. And it rarely reaches human affairs. Human affairs are way too complicated. In fact even understanding insects is an extremely complicated problem in the sciences. So the actual sciences tell us virtually nothing about human affairs." (2011, Science in the Dock)

Emile Durkheim:
"The category of class was at first indistinct from the concept of the human group; it is the rhythm of social life which is at the basis of the category of time; the territory occupied by the society furnished the material for the category of space; it is the collective force which was the prototype of the concept of efficient force, an essential element in the category of causality." (The Elementary Forms of the Religious Life, 1912)

Emile Durkheim:
"A social fact is every way of acting, fixed or not, capable of exercising on the individual an external constraint; or again, every way of acting which is general throughout a given society, while at the same time existing in its own right independent of its individual manifestations." (Rules of Sociological Method, 1895)

Emile Durkheim:
"When, then, the sociologist undertakes the investigation of some order of social facts, he must endeavour to consider them from an aspect that is independent of their individual manifestations." (Rules of Sociological Method, 1895)

Michel Foucault:
"Madness had become a thing to be observed, no longer the monster within, but an animal moved by strange mechanisms, more beast than man, where all humanity had long since disappeared." (History of Madness, 1961)

Michel Foucault:
"The disappearance of public executions marks therefore the decline of the spectacle; but it also marks a slackening of the hold on the body." (Discipline and Punish, 1977)

Michel Foucault:
"Not only must people know, they must see with their own eyes. Because they must be made to be afraid..." (Discipline and Punish, 1977)

Michel Foucault:
"I try to carry out the most precise and discriminative analyses I can in order to show in what ways things change, are transformed, are displaced. When I study the mechanisms of power, I try to study their specificity... I admit neither the notion of a master nor the universality of his law." (Dits de Ecrits, 1976)

Michel Foucault:
"Sometimes, because my position has not been made clear enough, people think I'm a sort of radical anarchist who has an absolute hatred of power. No! What I am trying to do is to approach this extremely important and tangled phenomenon in our society, the exercise of power, with the most reflective , and I would say prudent attitude." (Interview in the History of the Present, 1988)

Northrop Frye:
"The civilization we live in at present is a gigantic technological structure, a skyscraper almost high enough to reach the moon." (The Educated Imagination, 1963)

Thomas Hobbes:
"The office of the sovereign, be it a monarch or an assembly, consisteth in the end for which he was trusted with the sovereign power, namely the procuration of the safety of the people, to which he is obliged by the law of nature." (The Leviathan, 1651)

Thomas Hobbes:
"For by Art is created that great Leviathan called a Common-Wealth or State, (in latine Civitas) which is but an Artificiall Man; though of greater stature and strength than the Naturall, for whose protection and defence it was intended; and in which the Soveraignty is an Artificiall Soul, as giving life and motion to the whole body..." (The Leviathan, 1651)

Ibn Khaldun:
"When civilization [population] increases, the available labor again increases. In turn, luxury again increases in correspondence with the increasing profit, and the customs and needs of luxury increase. Crafts are created to obtain luxury products. The value realized from them increases, and, as a result, profits are again multiplied in the town." (Muqaddimah, 1377)

Ibn Khaldun:
"Businesses owned by responsible and organized merchants shall eventually surpass those owned by wealthy rulers." (Muqaddimah, 1377)

Ibn Khaldun:
"When incentive to acquire and obtain property is gone, people no longer make efforts to acquire any... Those who infringe upon property rights commit an injustice." (AZQuotes.com)

Niccolo Machiavelli:
"The chief foundations of all states, new as well as old or composite, are good laws and good arms; and as there cannot be good laws where the state is not well armed, it follows that where they are well armed, it follows that where they are well armed they have good laws." (The Prince, 1513)

Niccolo Machiavelli:
"...it is necessary to whoever arranges to found a Republic and establish laws in it, to presuppose that all men are bad and that they will use their malignity of mind every time they have the opportunity..." (Discourses on Livy, 1517)

Niccolo Machiavelli:
"You must know, then, that there are two methods of fighting, the one by law, the other by force: the first method is that of men, the second of beasts; but as the first method is often insufficient, one must have recourse to the second." (The Prince, 1513)

Niccolo Machiavelli:
"...one ought to be both feared and loved, but as it is difficult for the two to go together, it is much safer to be feared than loved, if one of the two has to be waning." (The Prince, 1513)

Niccolo Machiavelli:
"Upon this, one has to remark that men ought either to be well treated or crushed, because they can avenge themselves of lighter injuries, of more serious ones they cannot; therefore the injury that is to be done to a man ought to be of such a kind that one does not stand in fear of revenge." (The Prince, 1513)

Niccolo Machiavelli:
"Well-ordered states and wise princes have taken every care not to drive the nobles to desperation, and to keep the people satisfied and contented, for this is one of the most important objects a prince can have." (The Prince, 1513)

Niccolo Machiavelli:
"I say that every prince must desire to be considered merciful and not cruel. He must however, take care not to misuse this mercifulness." (The Prince, 1513)

John Stuart Mill:
"The only purpose for which power can be rightfully exercised over any member of a civilized community, against his will, is to prevent harm to others." (On Liberty, 1859)

John Stuart Mill:
"Society can and does execute its own mandates: and if it issues wrong mandates instead of right, or any mandates at all in thing with which it ought not to meddle, it practises a social tyranny more formidable than many kinds of political oppression, since, though not usually upheld by such extreme penalties, it leaves fewer means of escape, penetrating much more deeply into the details of life and enslaving the soul itself." (On Liberty, 1859)

Henri Poincare:
"Sociology is the science with the most methods and the least results." (Science and Method, 1908)

John Rawls:
"A just society is a society that if you knew everything about it, you'd be willing to enter it in a random place." (AZQuotes.com)

John Rawls:
"This organizing idea is that of society as a fair system of social cooperation between free and equal persons viewed as fully cooperating members of society over a complete life." (Political Liberalism, 1993)

John Rawls:
"In all sectors of society there should be roughly equal prospects of culture and achievement for everyone similarly motivated and endowed. The expectations of those with the same abilities and aspirations should not be affected by their social class." (A Theory of Justice, 1971)

John Rawls:
"The concept of justice I take to be defined, then, by the role of its principles in assigning rights and duties and in defining the appropriate division of social advantages." (A Theory of Justice, 1971)

John Rawls:
"A conception of justice cannot be deduced from self evident premises or conditions on principles; instead, its justification is a matter of the mutual support of many considerations, of everything fitted together into one coherent view." (A Theory of Justice, 1971)

Jean-Jacques Rousseau:
"The first man who, having enclosed a piece of ground, bethought himself of saying 'This is mine', and found people simple enough to believe him, was the real founder of civil society." (Discourse on Inequality, 1754)

Jean-Jacques Rousseau:
"You are undone if you once forget that the fruits of the earth belong to us all and the earth itself to nobody." (Discourse on Inequality, 1754)

Jean-Jacques Rousseau:
"Man is born free; and everywhere he is in chains. One thinks himself the master of others, and still remains a greater slave than they." (The Social Contract, 1762)

Jean-Jacques Rousseau:
"The Sovereign, being formed wholly of the individuals who compose it, neither has not can have any interest contrary to theirs." (The Social Contract, 1762)

Jean-Jacques Rousseau:
"Nothing is more dangerous than the influence of private interests in public affairs, and the abuse of laws by the government is a less evil than the corruption of the legislator." (The Social Contract, 1762)

Jean-Jacques Rousseau:
"It is solely on the basis of this common interest that every society should be governed." (The Social Contract, 1762)

Jean-Jacques Rousseau:
"In the strict sense of the term, a true democracy has never existed, and never will exist. It is against natural order that the great number should govern and that the few should be governed." (The Social Contract, 1762)

Jean-Jacques Rousseau:
"What man loses by the social contract is his natural liberty and an unlimited right to everything he tries to get and succeeds in getting; what he gains is civil liberty and the proprietorship of all he possesses." (The Social Contract, 1762)

Jean-Jacques Rousseau:
"The money that we possess is the instrument of liberty, that which we lack and strive to obtain is the instrument of slavery." (Confessions of Jean-Jacques Rousseau, 1782 posthumous)

Jean-Jacques Rousseau:
"A country cannot subsist well without liberty, nor liberty without virtue." (Quoted in A Dictionary of Thoughts by Tryon Edwards)

Jean-Jacques Rousseau:
"I love liberty, and I loathe constraint, dependence, and all their kindred annoyances." (Confessions of Jean-Jacques Rousseau, 1782 posthumous)

Jean-Jacques Rousseau:
"I well know that children ought to be kept employed, and that idleness is for them the danger most to be feared. But what should they be taught? This is undoubtedly an important question. Let them be taught what they are to practise when they come to be men; not what they ought to forget." (Discourse on the Sciences and Arts, 1750)

Aldolphe Quetelet:
"I believe that I have achieved to some extent what I have long said about the possibility of founding a social mechanics on the model established by celestial mechanics..." (Astronomie Elementarie? 1834)

Aldolphe Quetelet:
"Social Physics never can pretend to discover laws which will verify themselves in every particular, in the case of isolated individuals." (A Treatise on Man and the Development of his Faculties, 1842)

Aldolphe Quetelet:
"We are struck with the inflexible constancy of the laws which regulate the march of worlds and which preside over the succession of human generations." (Letter to H. R. H. the Grand Duke of Saxe Coburg and Gotha)

Aldolphe Quetelet:
"Moral phenomena, when observed o a great scale, are found to resemble physical phenomena." (A Treatise on Man and the development of His Faculties, 1842)

Aldolphe Quetelet:
"...we are under the domination of our habitudes, our wants, our social relations and a host of causes which, all of them, draw us in a hundred different ways." (A Treatise on Man and the development of His Faculties, 1842)

Aldolphe Quetelet:
"The time is come for studying the moral anatomy of also, and for uncovering its most afflicting aspects with the view of providing remedies." (A Treatise on Man and the development of His Faculties, 1842)

Aldolphe Quetelet:
"The collection of the laws, which exist independently of time and of the caprices of man, form a separate science which I have considered myself entitled to name social physics." (Quoted in Adolphe Quetelet Statistician by Frank Hamilton Hankins)

Carl Sagan:
"We live in a society absolutely dependent on science and technology and yet have cleverly arranged things so that almost no one understands science and technology. That's a clear prescription for disaster." (1994, Bringing Science Down to Earth)

L. K. Samuels:
"The field of economics is not exempt from the consequences of chaos and complexity. Marketplaces are indeterminant; value is subjective; and outcomes are subject to interpretation." (In Defense of Chaos, 2013)

Henry David Thoreau:
"The fate of the country does not depend on how you vote at the polls... it does not depend on what kind of paper you drop into the ballot-box once a year, but on what kind of man you drop from your chamber into the street every morning." (Slavery in Massachusetts, 1854)

Henry David Thoreau:
"A wise man will not leave the right to the mercy of chance, nor wish it to prevail through the power of the majority. There is but little virtue in the action of masses of men." (Civil Disobedience,  1849)

Henry David Thoreau:
"To speak practically and as a citizen unlike those who call themselves no-government men, I ask for, not at once no government, but at once a better government. Let every man make known what kind of government would command his respect, and that will be one step toward obtaining it." (Civil Disobedience,  1849)

Henry David Thoreau:
"I think that we should be men first, and subjects afterward. It is not desirable to cultivate a respect for the law, so much as for the right. The only obligation which I have a right to assume is to do at any time what I think right." (Civil Disobedience,  1849)

Voltaire:
"The institution of religion exists only to keep mankind in order, and to make men merit the goodness of God by their virtue." (Dictionnaire philosophique, 1764)

Voltaire:
"While loving glory so much how can you persist in a plan which will cause you to lose it?" (Letter to Frederick II of Prussia, 1757)

Voltaire:
"A minister of state is excusable for the harm he does when the helm of government has forced his hand in a storm; but in the calm he is guilty of all the good he does not do." (Le Siecle de Louis XIV, 1752)

Voltaire:
"Certainly any one who has the power to make you believe absurdities has the power to make you commit injustices. If you do not use the intelligence with which God endowed your mind to resist believing impossibilities, you will not be able to use the sense of injustice which God planted in your heart to resist a command to do evil."  (Questiones sur les miracles, 1765)

Voltaire:
"It is better to risk sparing a guilty person than to condemn an innocent one." (Zadig, 1747)

Voltaire:
"Let the punishments of criminals be useful. A hanged man is good for nothing; a man condemned to public works still serves the country, and is a living lesson." (Dictionnaire philosophique, 1785-1789)

Voltaire:
"What is tolerance? It is the consequence of humanity. We are all formed of frailty and error; let us pardon reciprocally each other's folly - that is the first law of nature." (Dictionnaire philosophique, 1764)

Max Weber:
"Sociology... is a science concerning itself with the interpretive understanding of social action and thereby with a causal explanation of its course and consequences. We shall speak of 'action' insofar as the acting individual attaches a subjective meaning to his behavior - be it overt or covert, omission or acquiescence. Action is 'social' insofar as its subjective meaning takes account of the behavior of others and is thereby oriented in its course." (Wikiquote)

Max Weber:
"Sociology is the science whose object is to interpret the meaning of social action and thereby give a causal explanation of the way in which the action proceeds and the effects which it produces. By 'action' in this definition is meant the human behaviour when and to the extent that the agent or agents see it as subjectively meaningful" (The Nature of Social Action, 1922)

E. O. Wilson:
"Cultural change is the statistical product of the separate behavioral responses of large numbers of human beings who cope as best they can with social existence." (On Human Nature, 1978)

E. O. Wilson:
"Cultural evolution is Lamarckian and very fast, whereas biological evolution is Darwinian and usually very slow." (On Human Nature, 1978)

E. O. Wilson:
"Few will doubt that humankind has created a planet sized problem for itself. No one wished it so, but we are the first species to become a geophysical force, altering Earth's climate, a role previously reserved for tectonics, sun flares, and glacial cycles. We are also the greatest destroyer of life since the ten-kilometer-wide meteorite that landed near Yucatan and ended the Age of Reptiles sixty-five million years ago." (Consilience: The Unity of Knowledge, 1998)

51. Subjective language

Aristotle:
"Poetry is finer and more philosophical than history; for poetry expresses the universal and history only the particular." (Poetics)

Gaston Bachelard:
"Poetry is one of the destinies of speech... One would say that the poetic image, in its newness, opens a future to language." (The Poetics of Reverie, 1960)

Gaston Bachelard:
"True poetry is a function of awakening. It awakens us, but it must retain the memory of previous dreams." (Water and Dreams, 1942)

Niels Bohr:
"But I myself find the division of the world into an objective and subjective side much too arbitrary. The fact that religions through the ages have spoken in images and parables and paradoxes means simply that there are no other ways of grasping the reality to which they refer." (Remarks after the Solvay Conference, 1927)

Niels Bohr:
"I consider those developments in physics during the last decades which have shown how problematic such concepts as 'objective' and 'subjective' are, a great liberation of thought." (Remarks after the Solvay Conference, 1927)

Niels Bohr:
"The objective world of 19th century science was, as we know today, an ideal limiting case, but not the whole reality." (Remarks after the Solvay Conference, 1927)

Niels Bohr:
"The great extension of our experience in recent years has brought light to the insufficiency of our simple mechanical conceptions and, as consequence, has shaken the foundation on which the customary interpretation of observation was based." (Atomic Physics and the Description of Nature, 1934)

Jacob Bronowski:
"The symbol and the metaphor are as necessary to science as poetry." (Science and Human Values, 1956)

Neils Bohr:
"I myself find the division of the world into an objective and a subjective side much too arbitrary the fact that religions through the ages have spoken in images, parables, and paradoxes means simply that there are no other ways of grasping the reality to which they refer. But that does not mean that it is not genuine reality. And splitting this reality into an objective and a subjective side won't get us very far." (Quoted in Physics and Beyond by Werner Heisenberg)

Niels Bohr:
"We must be clear that when it comes to atoms, language can be used only as in poetry. The poet, too, is not nearly so concerned with describing facts as with creating images and establishing mental connections." (1933, Discussions about Language)

Giannina Braschi:
"Poetry must find ways of breaking distance... All languages are dialects that are made to break new grounds." (Yo-Yo Boing! 1998)

Joseph Brodsky:
"By failing to read or listen to poets, society dooms itself to inferior modes of articulation, those of the population, the salesman,  or the charlatan. In other words, it forfeits its own evolutionary potential. For what distinguishes us from the rest of the animal kingdom is precisely this gift of speech. Poetry is not a form of entertainment and in a certain sense not even a form of art, but it is our anthropological, genetic goal. Our evolutionary, linguistic beacon." (Opening remarks as U.S Poet  Laureate, 1991)

Mario Bunge:
"At all times pseudo-profound aphorisms have been more popular than rigorous arguments." (Evaluating Philosophies, 2012)

Vannevar Bush:
"If scientific reasoning were limited to the logical processes of arithmetic we should not get far in our understanding of the physical world." (As We May Think, 1945)

Rachel Carson:
"If there is poetry in my book about the sea, it is not because I deliberately put it there, but because no one could write truthfully about the sea and leave out the poetry." (National Book Award for Nonfiction speech, 1952)

Samuel Taylor Coleridge:
"...poetry = the best words in their best order." (Table Talk, 1827)

Samuel Taylor Coleridge:
"Exclusively of the abstract science the largest and worthiest portion of our knowledge consists of aphorisms: and the greatest and best of men is but an aphorism." (Aids to Reflection, 1825)

Samuel Taylor Coleridge:
"No man was ever yet a great poet, without being at the same time a profound philosopher. For poetry is the blossom and the fragrance of all human knowledge, human thoughts, human passions, emotions and language." (Biographia Literia, 1817)

Aleister Crowley:
"True poetry is itself a magic spell which is key to the ineffable." (Eight lectures on Yoga, 1939)

Donald Davidson:
"I conclude that there is not such thing as language, not if a language is anything like what many philosophers and linguists have supposed. There is therefore no such thing to be learned, mastered or both with. We must give up the idea of clearly defined shared structure which language users acquire and then apply to cases. And we should try again to say how convention in any important sense is involved in language; or as I think, we should give up the attempt to illuminate how we communicate by appeal to conventions." (A Nice Derangement of Epitaphs, 1986)

Paul Engle:
"Poetry is ordinary language raised to the nth power. Poetry is boned with ideas, nerved and blooded with emotions, all held together by the delicate, tough skin of words." (New York Times, 1957)

Michael Faraday:
"I am no poet, but if you think for yourselves, as I proceed, the facts will form a poem in your minds." (Lecture Notes, 1858)

Richard Feynman:
"Pure mathematics is just such an abstraction from the real world, and pure mathematics does have a special precise language for dealing with its own special and technical subjects. But this precise language is not precise in any sense if you deal with real objects of the world, and it is only pedantic and quite confusing to use it unless there are some special subtleties which have to be carefully distinguished." (1965, New Textbooks for the New Mathematics)

Richard Feynman:
"Don't misunderstand me, there are many, many aspects of the world that mathematics is unnecessary for... but we were talking about physics... to not know mathematics is a severe limitation in understanding the world." (The Pleasure of Finding Things Out, 1999)

Christopher Fry:
"Poetry is the language in which man explores his own amazement." (Time, 1950)

Northrop Frye:
"We have to look at the figures of speech a writer uses, his images and symbols, to realize that underneath all the complexity of human life that uneasy stare at an alien nature is still haunting us..." (The Educated Imagination, 1963)

Johann Wolfgang von Goethe:
"They forgot that science arose from poetry, and failed to see that a change of times might beneficently reunite the two as friends, at a higher level and to mutual advantage." (On Morphology, 1817)

Stephen Jay Gould:
"Our mind works largely by metaphor and comparison, not always (or often) by relentless logic." (Bully for Brontosaurus, 1991)

Stephen Jay Gould:
"...metaphor is often the best agent of conceptual transition." (Bully for Brontosaurus, 1991)

Robert Graves:
"Abstract reason, formerly the servant of practical human reasons, has everywhere become its master and denies poetry any excuse for existence. Though philosophers like to define poetry as irrational fancy, for us it is practical, humorous, reasonable way of being ourselves." (The Crane Bag, 1969)

Johann Georg Hamann:
"Poetry is the mother tongue of the human race." (Samthliche Werken)

William Hazlitt:
"All that is worth remembering in life, is the poetry of it." (Lectures on the English Poets, 1818)

Georg W. F. Hegel:
"Poetry is the universal art of the spirit which has become free in itself and which is not tied down for its realization to external sensuous material; instead, it launches out exclusively in the inner space and the inner time of ideas and feelings." (Lectures on Aesthetics, 1835)

Martin Heidegger:
"All the poems of the poet who has entered into his poethood are poems of homecoming." (Existence and Being, 1949)

Werner Heisenberg:
"Light and matter are both single entities, and the apparent duality arises in the limitations of our language. It is not surprising that our language should be incapable of describing the processes occurring within the atoms, for, as has been remarked, it was invented to describe the experiences of daily life, and these consist only of processes involving exceedingly large numbers of atoms. Furthermore, it is very difficult to modify our language so that it will be able to describe these atomic processes, for words can only describe things of which we can form mental pictures, and this ability, too, is a result of daily experience. Fortunately, mathematics is not subject to this limitation." (Wikiquote)

William James:
"The union of the mathematician with the poet, fervor with measure, passion with correctness, this surely is the ideal." (Collected Essays and Reviews, 1920)

James Jeans:
"Today there is a wide measure of agreement, which on the physical side of science approaches almost to unanimity, that the stream of knowledge is heading towards a non-mechanical reality; the universe beings to look more like a great thought than like a great machine." (The Mysteries of the Universe, 1930)

Stainislaw Lem:
"As is known, the question of the objectivity or the subjectivity of probability has divided the world of science into two camps. Some maintain that there exists two types of probability, as above, others, that only subjective exists, because regardless of what is supposed to take place, we cannot have full knowledge of it." (A Perfect Vacuum, 1971)

Thomas Babington Macaulay:
"The merit of poetry, in its wildest forms, still consists in its truth - truth conveyed to the understanding, not directed by the words, but circuitously by means of imaginative associations which serve as its conductors." (Essays on the Athenian Orators)

James Clerk Maxwell:
"Mathematicians may flatter themselves that they posses new ideas which mere human language is yet unable to express. Let them make the effort to express these ideas in appropriate words without the aid of symbols, and if they succeed, they will not only lay us laymen under a lasting obligation, but we venture to say, they will find themselves very much enlightened during the process..." (Quoted in Thomson and Tait's Natural Philosophy, 1873)

Sallie McFague:
"A metaphor is a word used in an unfamiliar context to give us a new insight; a good metaphor moves us to see our world in an extraordinary way." (Speaking in Parables, 1975)

Oscar Morgenstern:
"All economic decisions, whether private or business, as well as those involving economic policy, have the characteristic that quantitative and non-quantitative information must be combined into one act of decision. It would be desirable to understand how these two classes of information can best be combined." (Quoted in Industrial Planning in France by McArthur and Scott)

Plato:
"A poet, you see, is a light thing, and winged and holy, and cannot compose before he gets inspiration and loses control of his senses and his reason has deserted him." (Goodreads.com)

Plato:
"Calligraphy is a geometry of the soul which manifests itself physically." (Goodreads.com)

Willard van Orman Quine:
"Language is a social art." (Goodreads.com)

Willard van Orman Quine:
"No two of us learn our language alike, nor, in a sense, does any finish learning it while he lives." (Goodreads.com)

Jane Roberts:
"Who needs poetry? All of us do. Poetry has always been the voice of the inner self, the carrier of revelations, dreams and visions that often defy expressions in ordinary prose." (Dialogues of the Soul and Mortal Self in Time, 1975)

Bertrand Russell:
"It must not be supposed that subjective elements are any less 'real' than the objective elements; they are only less important... because they do not point to anything beyond ourselves." (An Outline of Philosophy, 1927)

Socrates:
"I realized that it was not by wisdom that poets write their poetry, but by a kind of nature or inspiration, such as you find in seers and prophets..." (Quoted in The Apology by Plato)

Dylan Thomas:
"A good poem helps to change the shape and significance of the universe..." (Quite Early One Morning, 1954)

Frank Lloyd Wright:
"The scientist has marched in and taken the place of the poet. But one day somebody will find the solution to the problems of the world and remember, it will be a poet, not a scientist." (1959, Wikiquote)

52. Symbols

Pierre Duhem:
"Now, a symbol is not, properly speaking either true or false; it is, rather, something more or less well selected to stand for the reality it represents, and pictures that reality in a more or less precise or a more or less detailed manner." (The Aim and Structure of Physical Theory)

Clifford Geertz:
"To look at the symbolic dimensions of social action — art, religion, ideology, science, law, morality, common sense — is not to turn away from the existential dilemmas of life for some empyrean realm of de-emotionalized forms; it is to plunge into the midst of them." (1973, The Interpretations of Cultures)

Carl Jung:
"Not for a moment dare we succumb tot he illusion that an archetype can be finally explained and disposed of... The archetype - let us never forget this - is a psychic organ present in all of us." (The Psychology of the Child Archetype, 1941)

Carl Jung:
"Because there are innumerable things beyond the range of human understanding, we constantly use symbolic terms to represent concepts that we cannot define or fully comprehend." (Man and His Symbols, 1964 posthumous)

Charles W. Morris:
"Science and signs are inseparably interconnected since science both presents men with more reliable signs and embodies its results is systems of signs." (Foundations of the Theory of Signs, 1938)

Charles W. Morris:
"In this sense, he philosophy of the future will be semiotically oriented. But the nature of this influence will not always be the same, and will depend upon the role which given individuals and societies assign to scientific knowledge." (Signs, Language and Behavior, 1946)

Charles Sanders Peirce:
"But by 'semiosis' I mean on the contrary, an action, or influence, which is, or involves, a cooperation of 3 subjects, such as a sign, its object, and its interpretant, this tri-relative influence not being in any way resolvable into actions between pairs." (Pragmatism, 1907)

Charles Sanders Peirce:
"The entire universe is perfused with signs, if it is not composed exclusively of signs." (Quoted in Essays in Zoosemiotics by Thomas Sebeok)

Charles Sanders Peirce:
"A sign is in a conjoint relation to the thing denoted and to the mind." (On the Algebra of Logic, 1885)

Albert Pike:
"It is not the books of the philosophers, but in the religious symbolism of the ancients, that we must look for the footprints of science, and rediscover the mysteries of knowledge." (Morals and Dogma, 1871)

Fernand de Saussure:
"Thus we may found the science for the study of the life of signs against the background of social life; it would form part of social psychology and consequently of general psychology; we shall call it semiology (from Greek semeion - 'sign'). That science would explain to us in what signs consist of and by what laws they are governed." (Cours de Linguistique Generale, 1916)

Simone Weil:
"Concern for the symbol has completely disappeared from our science. And yet, if one were to give oneself the trouble, one could easily find, in certain parts at least of contemporary mathematics... symbols as clear, as beautiful, and as full of spiritual meaning as that of the circle and mediation. From modern thought to ancient wisdom the path would be short and direct, if one cared to take it." (The Need for Roots, posthumous)

53. Systematic Analysis

Gregory Bateson:
"As I see it, the advances in scientific thought come from a combination of loose and strict thinking, and this combination is the most precious tool of science." (Culture Contact and Schismogensis, 1935)

Thomas Edison:

"I speak without exaggeration when I say that I have constructed 3,000 different theories in connection with the electric light, each one of them reasonable and apparently likely to be true." (Talks with Edison)

Hesiod:

"It is best to do things systematically, since we are only human and disorder is our worst enemy." (Brainy Quote)

Zora Neale Hurston:
"Research is formalized curiosity. It is poking and prying with a purpose. It is a seeking that he who wishes may know the cosmic secrets of the world and they that dwell therein." (1942, Dust Tracks on a Road)

E. O. Wilson:
"The ideal scientist thinks like a poet and only later works like a bookkeeper." (Letters to a Young Scientist, 2013)

54. Thought

George Berkeley:
"The only thing we perceive are our perceptions." (Goodreads.com)

George Berkeley:
"It is indeed an opinion strangely prevailing amongst men, that houses, mountains, rivers, and in a word all sensible objects have an existence natural or real, distinct from their being perceived by the understanding." (A Treatise Concerning the Principles of Human Knowledge, 1710)

George Berkeley:
"Doth the reality of sensible things consist in being perceived? Or is it something distinct from being perceived, and that bears no relation to the mind?" (Three Dialogues between Hylas and Philonous, 1713)

David Bohm:
"Dialogue is really aimed at going into the whole thought process and changing the way the thought process occurs collectively. We haven't really paid much attention to thought as a process. We have engaged in thoughts, but we have only paid attention to the content, not the process." (On Dialogue)

Northrop Frye:
"It is clear that all verbal structures with meaning are verbal imitations of the elusive psychological and physiological processes known as thought..." (Anatomy of Criticism: Four Essays, 1957)

Georg W. F. Hegel:
"Any idea is a generalization, and generalization is a property of thinking. To generalize something means to think it." (Elements of the Philosophy of Right, 1820)

Mark Hopkins:
"Language is the picture and counterpart of thought." (Dedication of Williston Seminary, 1841)

David Hume:
"What peculiar privilege has this little agitation of the brain which we call thought, that we must thus make it the model of the whole universe." (Dialogues Concerning Natural Religion, 1779)

Michael C. Jackson:
"In modern systems approach, the concept 'system' is used not to refer to things in the world but to a particular way of organizing our thoughts about the world." (Creative Problem Solving: Total Systems Intervention, 1991)

Immanuel Kant:
"All human knowledge begins with intuitions, proceeds from thence to concepts and ends with ideas." (Critique of Pure Reason, 1781)

Letitia Elizabeth Landon:
"It is amazing how much a thought expands and refines by being put into speech: I should think it could hardly know itself." (Romance and Reality, 1831)

Karl Marx:
"Ideas do not exist separately from language." (Grundrisse, 1857)

Peter Miller, Martin Robson:
"Cognition is defined as non-rational, holistic, cognitive process that is enhanced by experience and associated with affect." (Australian Elite Leaders and Intuition, 2006)

Benjamin Peirce:
"When the formulas admit of intelligible interpretation, they are accessions to knowledge; but independently of their interpretation they are invaluable as symbolical expressions of thought." (On the Uses and Transformations of Linear Algebra, 1875)

Charles Sanders Peirce:
"The consciousness of a general idea has a certain 'unity of the ego' in it, which is identical when it passes from one mind to another." (Man's Glassy Essence, 1892)

Bernhard Riemann:
"With every simple act of thinking, something permanent, substantial, enters our soul. This substantial somewhat appears to us as a unit but (in so far so it is the expression of something extended in space and time) it seems to contain an inner manifoldness; I therefore name it 'mind-mass'. All thinking is, accordingly, formation of new mind masses." (Gesammelte Mathematische Werke, 1876)

Bernhard Riemann:
"Mind-masses, once formed, are imperishable, their combinations are indissoluble; only the relative strength of these combinations is altered by the incoming of new mind-masses." (Gesammelte Mathematische Werke, 1876)

Bernhard Riemann:
"Every mind-mass strives to produce a like formed mind-mass..." (Gesammelte Mathematische Werke, 1876)

Fernand de Saussure:
"Psychologically speaking out thought apart from its expression in words is only a shapeless indistinct mass. Philosophers and linguists have always agreed in recognizing that without the help of signs we would be unable to make clear cut, consistent distinction between two ideas. Without language, thought is a vague, uncharted nebula. There are not pre-existing ideas, and nothing is distinct before the appearance of language." (Cours de Linguistique Generale, 1916)

Fernand de Saussure:
"Thought, chaotic by nature, has to become ordered in the process of its decomposition." (Cours de Linguistique Generale, 1916)

Arthur Schopenhauer:
"For this perceptible and real world is obviously a phenomenon of the brain; and so in the assumption that the world as such might exist independently of all brains there lies a contradiction." (The World and Will as Representation, 1819)

P. F. Strawson:
"Part of my aim is to exhibit some general and structural features of the conceptual scheme in terms of which we think about particular things." (Individuals, 1959)

Elmer Towns:
"You don't really understand your thoughts until you express them in words." (How to Study and Teach the Bible, 1997)

Alan Watts:
"A person who thinks all the time has nothing to think about except thoughts. So he loses touch with reality, and lives in a world of illusion." (Alan Watts Teaches Meditation, 1992)

William Whewell:
"Fundamental ideas are not a consequence of experience, but a result of the particular constitution and activity of the mind, which is independent of all experience in its origin, though constantly combined with experience in its exercise." (Brainy Quote)

Ludwig Wittgenstein:
"The logical picture of the facts is the thought." (Tractatus Logico-Philosophicus, 1922)

Ludwig Wittgenstein:
"Without philosophy, thoughts are, as it were, cloudy and indistinct: its task is to make them clear and to give them sharp boundaries." (Tractatus Logico-Philosophicus, 1922)

55. Time

Francis Bacon:
"Time, which is the author of authors." (The Advancement of Learning, 1605)

Martin Heidegger:
"Being and time determine each other reciprocally, but in such a manner that neither can the former be addressed as something temporal nor can the latter be addressed as a being." (Brainyquote.com)

Martin Heidegger:
"Since time itself is not movement, it must somehow how have to do with movement. Time is initially encountered in those entities which are changeable; change is time." (The Concept of Time)

Ernst Mach:
"Of all the concepts which the natural inquirer employs, the simplest are the concepts of space and time." (Space and Geometry in the Light of Physiological, Psychological and Physical Inquiry, 1906)

Rollo May:
"The first thing necessary for a constructive dealing with time is to learn to live in the reality of the present moment. For psychologically speaking, this present moment is all we have." (Man's Search for Himself, 1953)

Henri Poincare:
"Time and space... it is not nature which impose them upon us, it is we who impose them upon nature because we find them convenient." (The Value of Science, 1905)

Leonardo da Vinci:
"Truth is the only daughter of time." (The Notebooks of Leonardo da Vinci, translated by Edward MacCurdy)

56. Truth

J. L. Austin:
"But suppose we take the noun 'truth': here is a case where the disagreements between different theorists have largely turned on whether they interpreted this as a name of a substance of a quality, or of a relation." (Philosophical Papers, 1979 posthumous)

Claude Bernard:
"A man of science rises ever, in seeking truth; and if he never finds it in its wholeness, he discovers nevertheless very significant fragments; and these fragments of universal truth are precisely what constitutes science." (Introduction à l'Étude de la Médecine Expérimentale, 1865)

Robert Boyle:
"And of universal nature, the notion I would offer, should be something like this. Nature is the aggregate of the bodies that make up the world, in its present state, considered as a principle, by virtue whereof, they act and suffer, according to the laws of motion prescribed by the author of things." (A Free Inquiry into the Vulgar Notion of Nature)

B. Cleasby:
"Truth and falsehood, it has been well said, are not always opposed to each other like black and white, but oftentimes and by design are made to resemble each other so as to be hardly distinguishable; just as the counterfeit things is counterfeit because it resembles the original thing." (Johnson v. Emerson, 1871)

Auguste Comte:
"It lays down, as is generally known, that our speculations upon all subjects whatsoever, pass necessarily through three successive stages: a Theological stage, in which free play is given to spontaneous fictions admitting of no proof; the Metaphysical stage, characterized by the prevalence of personified abstractions or entities; lastly, the Positive stage, based upon an exact view of the real facts of the case." (A General View of Positivism, 1848)

Donald Davidson:
"I thought... that the fact that in characterizing truth for a language it is necessary to put into relations with objects was enough to give some grip for the idea of correspondence; but this now seems to me a mistake. The mistake is in a way only a misnomer, but terminological infelicities have a way of breeding conceptual confusion, and so it is here. Correspondence theories have always been conceived as providing an explanation or analysis of truth, and this, a Tarski-style of truth, certainly does not do." (Quoted in Donald Davidson by Simon Evnin, 1991)

Rene Descartes:
"There is a need of a method for finding out the truth." (Rules for the Direction of the Mind, 1628)

Ludwig Feuerbach:
"We have busied ourselves and contented ourselves long enough with speaking and writing; now at least we demand that the word become flesh, the spirit matter; we are sick of political as we are of philosophical idealism; we are determined to become political materialists." (Lectures on the Essence of Religion, 1851)

Ludwig Feuerbach:
"I have always taken as the standard of the mode of teaching and writing, not the abstract, particular, professional philosopher, but universal man, that I have regarded man as the criterion of truth..." (The Essence of Christianity, 1841)

Gerald Ford:
"I believe that truth is the glue that holds government together, not only our government but civilization itself." (Remarks on Taking the Oath of Office, 1974)

Sigmund Freud:
"The voice of the intellect is a soft one, but it does not rest until it has gained a hearing." (The Future of an Illusion, 1927)

Galen:
"...as he approaches each particular problem, he should enquire into the premise needed for proving it..." (On the Doctrines of Hippocrates and Plato)

Carl Friedrich Gauss:
"In my opinion his distinction between analytic and synthetic theorems is such a one that either peters out in a triviality or is false." (Titan of Science by Guy Waldo Dunnington)

Ian Hacking:
"Why should there be the method of science? There is not just one way to build a house, or even to grow tomatoes. We should not expect something as motley as the growth of knowledge to be strapped to one methodology." (AZquotes.com)

George Wilhelm Friedrich Hegel:

"The enquiry into the essential destiny of Reason as far as it is considered in reference to the World is identical with the question, what is the ultimate design of the World?" (Lectures on the Philosophy of History, 1832)

Franz Kafka:
"Truth is indivisible, hence it cannot recognize itself; anyone who wants to recognize it has to be a lie." (The Zürau Aphorisms, posthumous)

Alexander Koyre:
"Yet the ways of thought, human thought, in its search for truth are, indeed, very strange." (Newtonian Studies, 1965)

Saul Kripke:
"Any necessary truth, whether a priori or a posteriori, could nit have turned out otherwise." (AZquotes.com)

Gottfried Wilhelm Leibniz:
"There are two kinds of truths: those of reasoning and those of fact. The truths of reasoning are necessary and their opposite is impossible; the truths of fact are contingent and their opposites are possible." (The Monadology, 1714)

Jean-Francois Lyotard:
"I define postmodern as incredulity towards metanarratives." (The Postmodern Condition: A Report on Knowledge, 1977)

Jean-Francois Lyotard:
"Knowledge is and will be produced in order to be sold, it is and will be consumed in order to be valorized in a new production..." (The Postmodern Condition: A Report on Knowledge, 1977)

Friedrich Nietzsche:
"What is truth? A movable host of metaphors, metonymies and anthropomorphisms: in short, a sum of human relations which have been poetically and rhetorically intensified, transferred, and embellished, and which after long usage, seem to a people to be fixed, canonical and binding. Truths are illusions which we have forgotten are illusions - they are metaphors that have become worn out and have been drained of sensuous force, coins which have lost their embossing and are now considered as metal and no longer as coins." (On Truth and Lies in a Nonmoral Sense, 1873)

Parmenides:
"We can speak and think only of what exists." (AZQuotes.com)

Blaise Pascal:
"God only pours out his light into the mind after having subdued the rebellion of the will by an altogether heavenly gentleness which charms and wins it." (The Art of Persuasion)

Pope John Paul II:
"Faith and reason are like two wings on which the human spirit rises to the contemplation of truth..." (Encyclical Fides et Ratio, 1998)

Pope John Paul II:
"Every truth - if it really is truth - presents itself as universal even if it is not the whole truth. If something is true, then it must be truth for all people and at all times." (Encyclical Fides et Ratio, 1998)

Willard van Orman Quine:
"A curious thing about the ontological problem is its simplicity. It can be put into three Anglo-Saxon monosyllables: 'What is there?' It can be answered, moreover, in a word - 'Everything' - and everyone will accept this answer as true." (On What There Is, 1948)

Baruch Spinoza:
"The more reality or being a thing has, the greater number of its attributes." (Ethics, 1677)

Alfred Tarski:
"The present article is almost wholly devoted to a single problem, the definition of truth. Its task is to construct - with reference to a given language - a materially adequate and formally correct definition of the term 'true sentence'. This problem, which belongs to the classical problems of philosophy, raises considerable difficulties. For although the meaning of the term 'true sentence' in colloquial language seems to be quite clear and unintelligible, all attempts to define this meaning more precisely have hitherto been fruitless, and many investigations in which this term has been used and which stated with apparently evident premises have often lead to paradoxes and antinomies (for which, however, a more or less satisfactory solution has been found). The concept of truth shares in this respect the fate of other analogous concepts in the domain of the semantics of language." (The Concept of Truth in Formalized Languages, 1931)

Henry David Thoreau:
"I went to the woods because I wished to live deliberately, to front only the essential facts of life..." (Walden, 1854)

Henry David Thoreau:
"A true account of the actual is the rarest poetry, for common sense always takes a hasty and superficial view." (A Week on the Concord and Merrimack Rivers, 1849)

Leonardo da Vinci:
"Fire may be represented as the destroyer of all sophistry, and as the image and demonstration of truth; because it is light and drives out darkness which conceals all essences [or subtle things]." (Quoted by The Notebooks of Leonardo da Vinci by Rudolf Flesch)

Jimmy Wales:
"Imagine a world in which every single person on the planet is given free access to the sum of all human knowledge. That's what we're doing." (Quoted in Wikimedia Founder Jimmy Wales Responds by Robin Miller 2004)

William Whewell:
"It is a test of true theories not only to account for but to predict phenomena." (Philosophy of the Inductive Sciences, 1840)

Alfred North Whitehead:
"There are no whole truths; all truths are half truths. It is trying to treat them as whole truths that plays the devil." (Dialogues, 1953)

Bernard Williams:
"Together with this demand for truthfulness, however, or (to put it less positively) this reflex against deceptiveness, there is an equally pervasive suspicion about truth itself: whether there is such a thing; if there is, whether it can be more than relative or subjective or something of that kind... The desire for truthfulness drives a process of criticism which weakens the assurance that there is any secure or unqualifiedly stateable truth." (Truth and Truthfulness, 2002)

Bernard Williams:
"[Nietzsche's] aim was to see how far the values of truth could be revalued, how they might be understood in a perspective quite different from the platonic and christian metaphysics which had provided their principle source in the west up to now." (Truth and Truthfulness, 2002)

Ludwig Wittgenstein:
"It is quite impossible for a proposition to state that it itself is true." (Tractatus Logico-Philosophicus, 1922)

Ludwig Wittgenstein:
"To convince someone of the truth, it is not enough to state it, but rather one must find the path from error to truth." (Philosophical Occasions, 1993 posthumous)

57. Understanding

Francis Bacon:
"The human understanding is unquiet; it cannot stop or rest, and still presses onward, but in vain. Therefore it is that we cannot conceive of any end or limit to the world, but always as of necessity it occurs to us that there is something beyond." (Novum Organum, 1620)

Noam Chomsky:
"You know, we have little bits of understanding, glimpses, a little bit of light here and there, but there's a tremendous amount of darkness which is a challenge." (Interview in Cardiff, 2011)

Rene Descartes:
"We ought to give the whole of our attention to the most insignificant and most easily mastered facts and remain a long time in contemplation of them until we are accustomed to behold the truth clearly and distinctly." (Rules for the Direction of the Mind, 1628)

Michael Dummet:
"Philosophy can take us no further than enabling us to command a clear view of the concepts by means of which we think about the world, and, by so doing, to attain a firmer grasp of the way we represent the world in our thought. It is for this reason and in this sense that philosophy is about the world." (The Logical Basis of Metaphysics, 1991)

Albert Einstein:
"By means of such concepts and mental relations between them, we are able to orient ourselves in the labyrinth of sense impressions." (Physics and Reality, 1936)

Albert Einstein:
"The aim of science is.. a comprehension, as complete as possible, of the connection between the sense experiences in their totality, and... the accomplishment of this aim by the use of the minimum of primary concepts and relations." (Autobiographical notes, 1949)

Albert Einstein:
"Fundamental ideas play the most essential role in forming a physical theory. Books on physics are full of complicated mathematical formulae. But thought and ideas not formulae, are the beginning of every physical theory. The idea must later take the mathematical form of a quantitative theory, to make possible the comparison of an experiment." (The Evolution of Physics, 1938)

T. S. Eliot:
"Men tighten the knot of confusion into perfect misunderstanding." (The Family Reunion, 1939)

Ludwig Feuerbach:
"The first philosophers were astronomers. The heavens remind man... that he is destined not merely to act, but also to contemplate." (The Essence of Christianity, 1841)

Paul Feyerabend:
"The best way of presenting such knowledge is the list - and the oldest scientific works were indeed lists of facts, parts, coincidences, problems in several specialized domains." (Farewell to Reason, 1987)

Northrop Frye:
"Literature is still doing the same job that mythology did earlier, but filling in its huge cloudy shapes with sharper lights and deeper shadows." (The Educated Imagination, 1963)

Hans-Georg Gadamer:
"Being that can be understood is language." (Truth and Method, 1960)

Carl Friedrich Gauss:
"By explanation the scientist understands nothing except the reduction of the least and simplest basic laws possible, beyond which he cannot go, but must plainly demand them; from them however he deduces the phenomena absolutely completely as necessary." (Quoted in Carl Friedrich Gauss: Titan of Science by Guy Waldo Dunnington)

Jurgen Habermas:
"The task of universal pragmatics is to identify and reconstruct universal conditions of possible mutual understanding." (On the Pragmatics of Communication, 1998)

Jurgen Habermas:
"Reaching and understanding is the process of bringing about an agreement on the presupposed basis of validity claims that are mutually recognized." (On the Pragmatics of Communication, 1998)

Martin Heidegger:
"Nevertheless, the ultimate business of philosophy is to preserve the force of the most elemental words in which Dasein expresses itself, and to keep the common understanding from leveling them off to that unintelligibilty which functions in turn as a source of pseudo-problems." (Being and Time, 1927)

Martin Heidegger:
"The great thinker is one who can hear what is greatest in the work of other 'greats' and who can transform it in an original manner." (Nietzsche, 1961)

Thomas Hobbes

"Understanding being nothing else, but conception caused by speech." (The Leviathan, 1651)

Edmund Husserl:
"Philosophers, as things now stand, are all too fond of offering criticism from on high instead of studying and understanding things from within." (Brainyquote.com)

Michael C. Jackson:
"In the modern systems approach, the concept 'system' is used not to refer to things in the world but to a particular way of organizing our thoughts about the world." (Creative problem solving: Total Systems Intervention, 1991)

Carl Jung:
"Every interpretation is hypothetical, for it is a mere attempt to read an unfamiliar text." (Modern Man in Search of a Soul, 1933)

Carl Jung:
"Man, as we realize if we reflect for a moment, never perceives anything fully or comprehends anything completely." (Man and His Symbols, 1964)

Franz Kafka:
"The right understanding of any matter and a misunderstanding of the same matter do not wholly exclude each other." (The Trial, 1920)

Joseph-Louis Lagrange:
"I regarded as quite useless the reading of large treatises of pure analysis: too large a number of methods pass at once before the eyes. It is in the works of application that one must study them; one judges their utility there and appraises the manner of making use of them." (Quoted in Moniteur Universel by J. F. Maurice)

John Locke:
"This is that which I think great readers are apt to be mistaken in; those who have read of everything, are thought to understand everything too; but it is not always so. Reading furnishes the mind only with materials of knowledge; it is thinking that makes what we read ours." (Quoted in Hand Book : Caution and Counsels by Horace Mann)

Thomas Robert Malthus:
"To minds of a certain cast there is nothing so captivating as simplification and generalization. (An Essay on the Principle of Population 2nd Edition, 1836)

Alfred Marshall:
"The most reckless and treacherous of all theorist is he who professes to let facts and figures speak for themselves." (AZ Quotes)

Dmitri Mendeleev:
"No law of nature, however general has been established all at once; its recognition has always been preceded by many presentiments." (AZquotes.com)

Marvin Minsky:
"What is the difference between merely knowing (or remembering, or memorizing and understating?) ... A thing or idea seems meaningful only when we have several different ways to represent it - different perspectives and different associations." (Music, Mind and Meaning, 1981)

Marvin Minsky:
"If we understood something just one way, we would not understand it at all." (Music, Mind and Meaning, 1981)

Marvin Minsky:
"You don't understand anything until you learn it more than one way." (Managing an Information Security and Privacy Awareness and training Program, 2005)

Michel de Montaigne:
"Since I would rather make of him an able man than a learned man, I would also urge that care be taken to choose a guide with a well-made rather than well-filled head." (Essais, 1580)

Linus Pauling:
"Life is too complicated to permit a complete understanding through the study of whole organisms. Only by simplifying a biological problem - breaking it down into a multitude of individual problems - can you get the answers." (Interview with Neil A. Campbell, 1986)

Jean Piaget:
"To express the same idea in still another way, I think that human knowledge is essentially active." (Brainy Quote)

Nicholas Rescher:
"I have never thought for a moment that if you cannot say it with numbers that it just is not worth saying. But all the same, I do firmly believe that where you cannot put numbers to work you will understand the matter better and more clearly for being able to explain why." (Epistemetrics, 2006)

John of Salisbury:
"Accurate reading on a wide range of subjects make the scholar; careful selection of the better makes the saint." (Policraticus, 1159)

Erwin Schrodinger:
"The scientific world-picture vouchsafes a very complete understanding of all that happens - it makes it just a little too understandable." (Nature and the Greeks, 1954)

Laurent Schwartz:
"At the end of the eleventh grade, I took the measure of the situation and came to the conclusion that rapidity doesn't have a precise relation to intelligence. What is important is to deeply understand things and their relations to each other. This is where intelligence lies. The fact of being quick or slow isn't really relevant. Naturally, it's helpful to be quick, like it is to have a good memory. But it's neither necessary nor sufficient for intellectual success." (A Mathematician Grappling with his Century, 2001)

John Searle:
"I want to block some common misunderstandings about 'understanding': in many of these discussions one finds a lot of fancy footwork about the word 'understanding'." (Minds, Brains and Programs, 1980)

Socrates:
"Employ your time in improving yourself by other men's writings, so that you shall gain easily what other have labored hard for." (Goodreads.com)

Socrates:
"Everything is plainer when spoken than when unspoken." (Quoted in Phaedrus by Plato)

Arthur Sulzberg:
"Information is now ubiquitous. Power is understanding." (Quoted in Information by Martin Kaiser)

Thales:
"A multitude of words is no proof of a prudent mind." (Quoted in The Lives of Eminent Philosophers by Diogenes Laertius)

John Vaughn:
"The witness swears more generally on his senses, the juror by collection and inference, by the act and force of his understanding." (Bushel's Case, 1670)

Simone Weil:
"I too have a growing inner certainty that there is a deposit of pure gold in me which ought to be passed on. The trouble is that I am more and more convinced by my experience and observation of my contemporaries that there is no one to receive it. It's a dense mass. What gets added to it is a piece with the rest. As the mass grows it becomes more and more dense. I can't parcel it into little pieces." (Lectures on Philosophy, 1959 posthumous)

Alfred North Whitehead:
"A philosopher of imposing stature doesn't think in a vacuum. Even their most abstract ideas are, to some extent conditioned by what is or is not known in the time when he lives." (Quoted in Dialogues of Alfred North Whitehead by Lucian Price)

Eugene Wigner:
"A mind of von Neumann's inexorable logic had to understand and accept much that most of us do not want to accept and do not even wish to understand." (Quoted in Year Book of the American Philosophical Society, 1958)

Charles Vert Willie:
"...Knowledge and understanding are complementary: one without the other is incomplete." (Five Black Soldiers, 1986)

58. Web of beliefs

Russell Ackoff:
"A problem never exists in isolation; it is surrounded by other problems  in space and time. The more of the context of a problem that a scientist can comprehend, the greater are his chances of finding a truly adequate solution." (The Development of Operations Research as a Science, 1956)

Aristotle:
"All teaching and all intellectual learning come about from already existing knowledge." (Posterior Analytics)

Rudolf Carnap:
"Science is a system of statements based on direct experience, and controlled by experimental verification. Verification in science is not, however, of single statements but of the entire system or a sub-system of statements." (The Unity of Science, 1934)

Rene Descartes:
"Each problem that I solved became a rule, which served afterwards to solve other problems." (Le Discours de la Methode, 1637)

Rene Descartes:
"Finally we ought to employ all the help of understanding, imagination, sense and memory, first for the purpose of having a distinct intuition of simple propositions; partly also in order to compare the propositions." (Rules for the Direction of the Mind, 1628)

William Fleming:
"Every truth has relation to some other. And we should try to write the facts of our knowledge so as to see them in their several bearings. This we do when we frame them into a system. To do so legitimately, we must begin by analysis and end with synthesis." (Quoted in Prose Quotations from Socrates to Macaulay by Austin Allibone)

Phillip Frank:
"Agreement with observe facts' never single singles out one individual theory. There is never only one theory  that is in complete agreement with all observed facts, but several theories that are in partial agreement. We have to select the final theory by compromise." (Philosophy of Science: The Link Between Science and Philosophy, 1957)

Richard Hamming:
"A solution which does not prepare for the next round with some increased insight is hardly a solution at all." (The Art of Doing Science and Engineering, 1997)

William James:
"The most violent revolutions in an individuals's belief leave most of his old order standing. Time and space, cause and effect, nature and history, and one's own biography remain untouched. New truth is always a go-between, a smoother-over of transitions. It marries old opinion to new fact so as ever to show a minimum of jolt, a maximum of continuity." (What Pragmatism Means. Lectures at the Lowell Institute and Columbia University, 1931)

William James:
"No philosophy can ever be anything but a summary sketch, a picture of the world in abridgment, a foreshadowed bird's eye view of the perspective of events." (A Pluralist Universe, 1909)

Carl Jung:
"Every concept in our conscious mind, in short, has its own psychic associations." (Man and His Symbols, 1964)

Immanuel Kant:
"Human reason is by nature architectonic." (Critique of Pure Reason, 1781)

Dennis Lindley:
"Facts form a sort of bedrock on which we can build the shifting sands on uncertainty." (Understanding Uncertainty, 2006)

Peter Medawar:
"We should think of [scientic inquiry] as a logically articulated structure of justifiable beliefs about nature." (Induction and Intuition in Scientific Thought, 1969)

Peter and Jean Medawar:
"A scientist is no more a collector and classifier of facts than historian is a man who compiles and classifies a chronology of the dates of great battles and major discoveries." (Aristotle to Zoos: A Philosophical Dictionary of Biology, 1985)

Richard von Mises:
"No contradiction exists, if the events are correctly interpreted." (Probability, Statistics and Truth, 1957)

Augustus De Morgan:
"New knowledge... must come by contemplation of old knowledge." (A Budget of Paradoxes, 1872)

Otto Neurath:
"Every new statement is to be confronted with existing ones, already brought to a state of harmony between themselves. A statement will be considered correct if it can be joined to them." (Soziologie im Physikalismus, 1931)

Friedrich Nietzsche:
"That immense framework and planking of concepts to which the needy man clings his whole life long in order to preserve himself is nothing but a scaffolding and toy for the most audacious feats of the liberated intellect." (On Truth and Lies in an Extra Moral Sense, 1873)

Ivan Pavlov:
"Learn, compare, collect the facts!" (Wikiquote)

Henri Poincare:
"The scientist must set in order. Science is built up with facts, as a house is with stones. But a collection of facts is no more a science than a heap of stones is a house." (Science and Hypothesis, 1901)

Elizabeth Prentiss:
"No truth can be said as it is until it is seen in its relation to all other truths. In this relation only is it true." (Quoted in Dictionary of Burning Words by Josiah Hotchkiss Gilbert)

Willard van Orman Quine:
"Implication is thus the very texture of our web of belief, and logic is the theory that traces it." (The Web of Belief, 1970)

Willard van Orman Quine:
"The totality of our so-called knowledge or beliefs, from the most casual matter of geography and history to the profoundest laws of atomic physics or even of pure mathematics and logic, is a man-made fabric which impinges on experience only along the edges." (AZquotes.com)

Willard van Orman Quine:
"Our acceptance of an ontology is, I think similar in principle to our acceptance of a scientific theory, say a system of physics; we adopt, at least insofar as we are reasonable, the simplest conceptual scheme into which the disordered fragments of raw experience can be fitted and arranged." (AZquotes.com)

Bernhard Riemann:
"Every entering mind-mass excites all related mind-masses..." (Gesammelte Mathematische Werke, 1876)

Bernhard Riemann:
"Forming mind-masses amalgamate, combine or compound themselves in definite degree, partly with each other, partly with older mind-masses." (Gesammelte Mathematische Werke, 1876)

Bertrand Russell:
"Reason is a harmonising, controlling force rather than a creative one. Even in the most purely logical realms, it is insight that first arrives at what is new." (Our Knowledge of the External World, 1914)

Bertrand Russell:
"Every man, wherever he goes, is encompassed by a cloud of comforting convictions, which move with him like flies on a summer day." (Sceptical Essays, 1928)

Antonin Sertillanges:
"We never think alone; we think in company, in a vast collaboration; we work with the wonders of the past and of the present." (The Intellectual Life, 1920)

John Sowa:
"A conceptual graph is a finite connected bipartite graph which consists of concepts and conceptual relations. Every conceptual relation has one or more arcs each of which is linked to a concept." (Conceptual Structures, 1984)

John Sowa:
"We define a semantic network as 'the collection of all the relationships that concepts have to other concepts, to precepts, to procedures, and to the motor mechanisms' of the knowledge." (Conceptual Structures, 1984)

Alfred North Whitehead:
"Systems, scientific and philosophic come and go. Each method of limited understanding is at length exhausted. In its prime, each system is a triumphant success: in its decay it is an obstructive nuisance." (Adventures of ideas, 1933)

Ludwig Wittgenstein:
"Don't get involved in partial problems, but always take flight to where there is a free view over the whole single great problem, even if this view is still not a clear one." (Notebooks 1914-1916)

Ludwig Wittgenstein:
"All testing, all confirmation and disconfirmation of a hypothesis takes place already within a system." (On Certainty, 1969 posthumous)

Ludwig Wittgenstein:
"The child learns to believe a host of things, i.e. it learns to act according to those beliefs. Bit by bit there forms a system of what is believed, and in that system, some things stand unshakably fast and some are more or less liable to shift. What stands fast does so, not because it is intrinsically obvious or convincing; it is rather held fast by what lies around it." (On Certainty, 1969 posthumous)

Ludwig Wittgenstein:
"What I hold fast to is not one proposition but a nest of propositions." (On Certainty, 1969 posthumous)

59. Word confusion

J. L. Austin:
"Words are not (except in their own little corner) facts or things: we need therefore to prise them off the world, to hold them apart from and against it, so that we can realize their inadequacies and arbitrariness and can relook at the world without blinkers." (Philosophical Papers, 1979 posthumous)

J. L. Austin:
"After all we speak of people 'taking refuge' in vagueness - the more precise you are, in general the more likely you are to be wrong, whereas you stand a good chance of not being wrong if you make it vague enough." (Sense and Sensibilia, 1962 posthumous)

Francis Bacon:
"Words plainly force and overrule the understanding, and throw all into confusion, and lead men away into numberless empty controversies and idle fancies." (Novum Organum, 1620)

Francis Bacon:
"The human understanding is of its own nature prone to suppose the existence of more order and regularity in the world than it finds." (Novum Organum, 1620)

George Berkeley:
"In the pursuit of truth we must beware of being misled by terms which we do not rightly understand, That is the chief point. Almost all philosophers utter the caution; few observe it." (De Motu, 1721)

George Berkeley:
"Upon the whole, I am inclined to think that the far greater part, if not all, of those difficulties which have hitherto amuse philosophers, and blocked up the way to knowledge, are entirely owing to our selves. That we have first raised a dust, and the complain, we cannot see." (AZquotes.com)

George E. P. Box:
"Essentially, all models are wrong, but some are useful." (Empirical Model Building and Response Surfaces, 1987)

Robert Boyle:
"Among Latin writers, the acceptations of the word 'nature' are so many, that I remember, one author reckons up no less than fourteen or fifteen... the very great ambiguity of this term, and the promiscuous use made of it, without sufficiently attending to its different significations, render many of the expressions wherein tis employed either unintelligible, improper, or false. " (A Free Inquiry into the Vulgar Notion of Nature)

John Dalton:
"Berzelius' symbols are horrifying... They appear to me equally to perplex the adepts in science, to discourage the learner, as well as to cloud the beauty and simplicity of the atomic theory. " (AZQuotes.com)

Jacques Derrida:
"Differance is the systematic play of differences, of the traces of differences, of the spacing by means of which elements are related to each other." (Positions, 1982)

Jacques Derrida:
"The 'a' of differance also recalls that spacing is temporization, the detour and postponement by means of which intuition, perception, consummation - a word, the relationship to the present, the reference to a present reality, to a being - are always deffered." (Positions, 1982)

Albert Einstein:
"Concepts that have proven useful in ordering things easily achieve such an authority over us that we forget their early origins and accept them as unalterable givens. Thus they come to be stamped as 'necessities of thought', 'a priori givens' etc... The path of scientific advance is often made impassible for a long time through such errors." (Ernst Mach Memorial Notice, 1916)

Jurgen Habermas:
"The speaker must choose a comprehensible [verstandlich] expression so that the speaker and hearer can understand another." (Quoted in Critical Heuristics of Social Plannino by Werner Ulrich)

Jacques Lacan:
"I always speak the truth. Not the whole truth, because there's no way, to say it all. Saying it all is literally impossible: words fail. Yet it's through this very impossibility that the truth holds onto the real." (Goodreads.com)

Jacques Lacan:
"The real is what resists symbolization absolutely." (The Seminar of Jacques Lacan: Freud's Papers on Technique)

Guiseppe Peano:
"Ambiguity of language is philosophy's main source of problems. That is why it is of the utmost importance to examine attentively the very words we use." (Arthmetices Principia Nova Methodo Exposita, 1889)

John Ruskin:
"Say all you have to say in the fewest possible words, or your reader will be sure to skip them; and in the plainest possible words or he will certainly misunderstand them." (A Joy for Ever, 1857)

Herbert Spencer

"How often misused words generate misleading thoughts." (Brainy Quote)

Simone Weil:
"We have seen that language is something precious because it allows us to express ourselves; but it is fatal when one allows oneself to be completely led astray by it, because then it prevents us from expressing oneself. Language is the source of the prejudices and haste which Descartes thought of as the source of error." (Lectures on Philosophy, 1959)

Morris West:
"Ever since the Greeks, we have been drunk with language! We have made a cage with words and shoved our God inside!" (The Heretic, 1968)

60. Word creation

A. J. Ayer:
"I see philosophy as a fairly abstract activity, as concerned mainly with the analysis of criticism and concepts, and of course most usefully of scientific concepts." (Quoted in A.J Ayers: A Life by Ben Rogers)

J. L. Austin:
"Our common stock of words embodies all the distinctions men have found worth drawing, the connexions they have found worth marketing, in the lifetimes of many generations; these surely are likely to be more numerous, more sound, since they have stood up to the long test of the survival of the fittest, and more subtle, at least in all ordinary and reasonably practical matter, than any that you or I are likely to think up in our arm-chairs of an afternoon..." (AZquotes.com)

Gaston Bachelard:
"A systematic revolution of basic concepts begins with Einsteinian science. In the very detail of its concepts a relativism of the rational and the empirical is established. Science then undergoes what Nietzsche called 'an upheaval of concepts' as if the Earth, the universe, things professed a different structure from the fact that their explanation rests upon new foundations." (The Philosophic Dialectic of the Concepts of Relativity, 1949)

Isiah Berlin:
"To confuse our own constructions and inventions with eternal laws or divine decrees is one of the most fatal delusions of man." (Essays in Honour of E. H. Carr, 1974)

David Bohm:
"For the history of scientific research is full of examples in which it was very fruitful indeed to assume that certain objects or elements might be real..." (A Suggested Interpretation of Quantum Theory in Terms of Hidden Variables, 1952)

David Bohm:
"Of course, we must avoid postulating a new element for each new phenomenon. But an equally serious mistake is to admit into the theory only those elements which can now be observed." (A Suggested Interpretation of Quantum Theory in Terms of Hidden Variables, 1952)

Rudolf Carnap:
"The task of making more exact a vague or not quite exact concept used in everyday life or in an earlier stage of scientific or logical development or rather of replacing it by a newly constructed, more exact concept, belongs among the most important tasks of logical analysis and logical construction. We call this the task of explicating..." (Meaning and Necessity, 1947)

Rudolf Carnap:
"After new forms are introduced into the language, it is possible to formulate, with their help internal questions and possible answers to them." (Empiricism, Semantics and Ontology, 1950)

Rudolf Carnap:
"To be sure, we have to face at this point, an important question; but it is a practical, not a theoretical question; it is the question of whether or not to accept the new linguistic forms. The acceptance cannot be judged as being either true or false because it is not an assertion. It can only be judged as being more or less expedient, fruitful, conductive to the aim for which the language is introduced." (Empiricism, Semantics and Ontology, 1950)

Albert Einstein:
"I believe that the first step in the setting of a 'real external world' is the formation of the concept of bodily objects... out of the multitude of our sense experiences we take, mentally and arbitrarily, certain repeatedly occurring complexes of sense impressions... and we correlated them a concept - the concept of a bodily object." (Physics and Reality, 1936)

Gottlob Frege:
"We suppose, it would seem, that concepts grow in the individual mind like leaves on a tree, and we think to discover their nature by studying their growth; we seek to define them psychologically, in terms of the human mind. But this account makes everything subjective, and we follow it through to the end, does away with truth." (Grundgesetze der Arithmetik, 1893)

Gottlob Frege:
"Often it is only after immense intellectual effort, which may have continued over centuries, that humanity at last succeeds in achieving knowledge of a concept in its pure form, by  stripping off the irrelevant accretions which veil it from the eye of the mind." (Grundgesetze der Arithmetik, 1893)

Gottlob Frege:
"It really is worth the trouble to invent a new symbol if we can thus remove not a few logical difficulties and ensure the rigor of the proofs." (Quoted in Readings in Epistemology by Dagobert David Runes)

Carl Friedrich Gauss:
"I am almost amazed that you consider a professional philosopher capable of no confusion in concepts and definitions. Such things are nowhere more at home than among philosophers who are not mathematicians..." (Titan of Science by Guy Waldo Dunnington)

Stephen Jay Gould:
"The  nature of true genius must lie in the elusive capacity to construct these new modes from apparent darkness." (The Flamingo's Smile, 1985)

Werner Heisenberg:
"It is not surprising that out language should be incapable of describing the processes occurring within the atoms, for, as has been remarked, it was invented to describe the experiences of daily life, and these consist only of processes involving exceedingly large number of atoms." (The Physical Principles of Quantum Theory, 1930)

Werner Heisenberg:
"The existing scientific concepts cover always only a very limited part of reality, and the other part that has not yet been understood is infinite." (Physics and Philosophy, 1958)

David Hilbert:
"To new concepts, correspond necessarily, new signs. These we choose in such a way that they remind us of the phenomena which were the occasion for the formation of the new concept." (Mathematical Problems, 1900)

David Hume:
"We may change the name of things; but their nature and their operation on the understanding never change." (An Enquiry Concerning Human Understanding, 1748)

Soren Kierkegaard:
"In vain do individual great men seek to mint new concepts and to set them in circulation - it is pointless. They are used for only a moment, and not by many, either, and they merely contribute to making the confusion even worse..." (The Journals of Søren Kierkegaard, 1835)

Antoine Lavoisier:
"As ideas are preserved and communicated by means of words, it necessarily follows that we cannot improve the language of any science without at the same time improving the science itself; neither can we, on the other hand improve a science without improving the language or nomenclature which belongs to it." (Elements of Chemistry, 1790)

Antoine Lavoisier:
"It is impossible to disassociate language from science or science from language, because every natural science always involves three things: the sequence of phenomena on which the science is based; the abstract concepts which call these phenomena to mind; and the words in which the concepts are expressed." (Traite Elementarie de Chimie, 1789)

Antoine Lavoisier:
"Thus, while I thought myself employed only in forming a Nomenclature, and while I proposed to myself nothing more than to improve the chemical language, my work transformed itself by degrees, without my being able to prevent it, into a treatise upon the Elements of Chemistry." (Elements of Chemisty, 1790)

Richard Leakey:
"A vital leap in the evolution of intellectual capacity would have been the ability to form concepts, to conceive of individual objects as belonging to distinct classes, and thus do away with the almost intolerable burden of relating one experience to another. Concepts, moreover, can be manipulated and this is the root of abstract thought and of invention. The formation of concepts is also a necessary, but apparently not sufficient, condition for the emergence of language." (1977, Origins)

Carl Linnaeus:
"The first step in wisdom is to know the things themselves; this notion consists in having a true idea of the objects; objects are distinguished and known by classifying them methodologically and giving them appropriate names." (System Naturae, 1735)

Carl Linnaeus:
"Nomenclature, the other foundation of botany, should provide the names as soon as the classification is made... If the names are unknown, knowledge of the thing also perishes." (Philosohia Botanica, 1751)

Carl Linnaeus:
"Botany is based on fixed genera." (Philosohia Botanica, 1751)

Carl Linnaeus:
"The names of the plants ought to be stable, consequently they should be given to stable genera." (Philosohia Botanica, 1751)

Ernst Mach:
"Nature consists of the elements given by the senses. Primitive man first takes out of them certain complexes of these elements that present themselves with a certain stability and are most important to him. The first and oldest words are names for things." (The Analysis of Sensations, 1902)

Benoit Mandlebrot:
"People want to see patterns int the world. It is how we evolved. We descended from those primates who were best at spotting the telltale pattern of a predator in the forest or of food in the Savannah. So important is this skill that we apply it everywhere, warranted or not." (Quoted in the Misbehavior of the Markets by Richard Hudson)

Karl Mannheim:
"In order to be transmuted into knowledge, every perception is and must be ordered and organized into categories." (Ideology and Utopia, 1929)

Ernst Mayr:
"Biological classifications have two major objectives: to serve as a basis of biological generalizations in all sort of comparative studies and to serve as key information storage system." (Quoted in Ontological foundations in knowledge organization)

Marvin Minsky:
"Just knowing that such states exist, that is, having symbols for them, is half the battle." (Music, Mind and Meaning, 1981)

Friedrich Nietzsche:
"Everything which distinguishes man from the animals depends on this ability to volatilize perceptual metaphors in a schema and thus to dissolve an image into a concept." (On Truth and Lies in an Extra Moral Sense, 1873)

Friedrich Nietzsche:
"We have seen how it is originally language which works on the construction of concepts, a labor taken over in later ages by science." (On Truth and Lies in an Extra Moral Sense, 1873)

Friedrich Nietzsche:
"The drive toward the formation of metaphors is the fundamental human drive, which one cannot for a single instant dispense with in though, for one would thereby dispense with man himself." (On Truth and Lies in an Extra Moral Sense, 1873)

T. Overbury:
"Things were first made, then words." (A Wife)

Charles Sanders Peirce:
"The one primary and fundamental law of mental action consists in a tendency to generalization." (The Architecture of the Theories, 1891)

Jordan Peterson:
"A thing isn't quite real until you name it." (Wikiquote)

Willard van Orman Quine:
"Linguistically, and hence conceptually, the things in sharpest focus are the things that are public enough to be talked of publicity, common and conspicuous enough to be talked of often, and near enough to sense to be quickly identified and learned by name..." (AZquotes.com)

Willard van Orman Quine:
"We cannot stem linguistic change, but we can drag our feet." (Goodreads.com)

Arthur Schopenhauer:
"[Reason] can only give after it has received. Of itself it has nothing but the empty forms of its operation... Concepts in general only exist after experience of ideas of perception, and as their whole nature consists in their relation to these, it is clear that they presuppose them." (The World and Will as Representation, 1819)

Edward Witten:
"Most people who haven't been trained in physics probably think of what physicists do as a question of incredibly complicated calculations, but that's not really the essence of it. The essence of it is that physics is about concepts, wanting to understand the concepts, the principles by which the world works." (Interview with P. W. C. Davies and Julian Brown, 1992)

Gene Wolfe:
"Evolution teaches us the original purpose of language was to ritualize man's threats and curses, his spells to compel the gods; communication came later." (The Death of Doctor Island, 1973)

61. Word meaning

Alfred Alder:
"Meanings are not determined by situations, but we determine ourselves by the meanings we give to situations." (Brainy Quote)

Aristotle:
"It is the mark of an educated man to look for precision in each class of things just so far as the nature of the subject admits." (Nicomachean Ethics)

Isaac Asimov:
"The machine is only a tool after all, which can help humanity progress faster by taking some of the burdens of calculations and interpretations off its back. The task of the human brain remains what it has always been; that of discovering new data to be analyzed, and of devising new concepts to be tested." (I, Robot, 1950)

J. L. Austin:
"Philosophers often seem to think that they can just 'assign' any meaning whatever to any word; and so no doubt, in an absolutely trivial sense, they can (like Humpty-Dumpty)." (Sense and Sensibilia, 1962 posthumous)

J. L. Austin:
"Faced with the nonsense question, 'what is the meaning of a word?' and perhaps dimly recognizing it to be nonsense, we are nevertheless not inclined to give it up." (Philosophical Papers, 1979 posthumous)

A. J. Ayer:
"There is philosophy, which is about conceptual analysis (about the meaning of what we say) and there is all of this... all of life." (Quoted in A.J.  Ayer: A Life by Ben Rogers)

Niels Bohr:
"We are suspended in language in a way that we cannot say what is up and what is down. The word 'reality' is also a word, and a word which we must learn to use correctly." (Quoted in Philosophy of Science, Vol. 37, 1934)

Rudolf Carnap:
"The main problem of this book is the development of a new method for the semantical analysis of meanings of linguistic expressions. This method, called the method of extension and intension, is developed by modifying the extending certain customary concepts, especially those of class and property." (Meaning and Necessity, 1947)

Rudolf Carnap:
"Frege's pair of concepts (nominatum and sense) is compared with out pair (extension and intension)."  (Meaning and Necessity, 1947)

Collin Cherry:
"The theory of communication is partly concerned with the measurement of information content of signals, as their essential property in the establishment of communication links." (On Human Communication, 1957)

Jacques Derrida:
"...the central signified, the original or transcendental signified, is never absolutely present outside a system of differences. The absence of the transcendental signified extends the domain and the interplay of signification ad infinitum." (Structure, Sing and Play in the Discourse of Human Sciences, 1966)

Jacques Derrida:
"The entire history of the concept of structure, before the rupture of which we are speaking, must be thought of a series of substitutions of center for center." (Structure, Sing and Play in the Discourse of Human Sciences, 1966)

Jacques Derrida:
"Therefore we will not listen to the source itself in order to learn what it is or what it means, but rather to the turns of speech, the allegories, figures, metaphors, as you will, into which the source has deviated, in order to lose it or rediscover it - which always amounts to the same." (Goodreads.com)

Emile Durkheim:
"Now, it is unquestionable that language, and consequently the system of concepts which it translates, is the product of a collective elaboration. What it expresses is the manner in which society as a whole represents the facts of experience. The ideas which correspond to the diverse elements of language are thus collective representations." (The Elementary Forms of the Religious Life, 1912)

Emile Durkheim:
"At the roots of all our judgments there are a certain number of essential ideas which dominate all our intellectual life; they are what philosophers since Aristotle have called the categories of the understanding: ideas of time, space, class, number, cause, substance, personality, etc. They correspond to the most universal properties of things." (The Elementary Forms of the Religious Life, 1912)

Albert Einstein:
"Concepts have meaning only if we can point to objects to which they refer and to rules by which they are assigned to these objects." (Ernst Mach Memorial Notice, 1916)

Ludwig Andreas Feuerbach:
"The present age.. prefers the sign to the thing signified, the copy to the original, fancy to reality, the appearance to the essence... for in these days illusion only is sacred, truth profane." (The Essence of Christianity, 1841)

Stanley Fish:
"Language is not a handmaiden to perception; it is perception; it gives shape to what would otherwise be inert and deal." (How to Write a Sentence and How to Read One, 2011)

Felix Frankfurter:
"All our work, our whole life is a matter of semantics, because words are the tools with which we work, the material out of which laws are made, out of which the constitution was written. Everything depends on our understanding of them." (Quoted in Readers Digest, 1964)

Hans-Georg Gadamer:
"Kripke tries to sober us up by denying that meaning determines reference... They are not abbreviation for descriptions, but (in Kripke's coinage) 'rigid designators' - that is, they would name the same things in any possible world, including words in which they bearers did not have the properties we, in this world, use to identify them." (Kripke vs. Kant, 1980)

Johann Wolfgang von Goethe:
"Hypotheses are scaffoldings erected in front of a building and then dismantled when the building is finished. They are indispensable for the workman; but you mustn't mistake the scaffolding for the building." (Maxims and Reflections, 1833)

Thomas Hobbes:
"For it is not the bare Words, but the Scope of the writer that giveth true light, by which any writing is to interpreted..." (The Leviathan, 1651)

Saul Kripke:
"Let's call something a rigid designator if in every possible world it designates the same object..." (AZquotes.com)

Saul Kripke:
"If I use the name 'Hesperus' to refer to a certain planetary body when seen in a certain celestial position in the evening, it will not therefore be a necessary truth that Hesperus is ever seen in that evening. That depends on various contingent facts about the people being there to see and things like that." (Naming and Necessity, 1980)

Jacques Lacan:
"Meaning is produced not only by the relationship between the signifier and the signified but also, crucially, by the position of the signifiers in relation to other signifiers." (Goodreads.com)

Jacques Lacan:
"Nature provides - I must use the word - signifies, and these signifies organize human relation in a creative way, providing them with structures and shaping them." (The Four Fundamental Concepts of Psycho Analysis, 1978)

Jacques Lacan:
"For the signifier is a unit in its very uniqueness, being by nature symbol only of an absence." (AZQuotes.com)

Amy Lowell:
"My words are little jars for you to take and put upon a shelf. Their shapes are quaint and beautiful, and they have many pleasant colors and lusters to recommend them." (A Gift)

Marshall McLuhan:
"All words, in every language, are metaphors." (Laws and Media: The New Science, 1988)

Friedrich Nietzsche:
"We believe that we know something about the things themselves when we speak of trees, colors, snow and flowers; and yet we possess nothing but metaphors for things - metaphors which correspond in no way to the original entities." (On Truth and Lies in an Extra Moral Sense, 1873)

Friedrich Nietzsche:
"Every concept arises from the equation of unequal things. Just as it is certain that one leaf is never totally the same as another, so it is certain that the concept 'leaf' is formed by arbitrarily discarding these individual differences and by forgetting the distinguishing aspects." (On Truth and Lies in an Extra Moral Sense, 1873)

Friedrich Nietzsche:
"We obtain the concept, as we do the form, by overlooking what is individual and actual; whereas nature is acquainted with no forms and no concepts, and likewise with no species, but only an X which remains inaccessible and undefinable for us." (On Truth and Lies in an Extra Moral Sense, 1873)

C. K. Ogden, I. A. Richards:
"It might... have been supposed that logicians and psychologists would have devoted special attention to meaning, since it is so vital for all the issues with which they are concerned. But this is not the case..." (The Meaning of Meaning, 1923)

Blaise Pascal:
"The world is satisfied with words. Few appreciate the things beneath." (Lettes Provinciales)

Charles Sanders Peirce:
"Of this nature are all natural signs and physical symptoms. I call such a index a pointing finger being the type of the class. The index asserts nothing; it only says 'there!'. It takes hold of our eyes as it were, and forcibly directs them to a particular object, and there it stops." (On the Algebra of Logic, 1885)

Willard van Orman Quine:
"The world 'definition' has come to have a dangerously reassuring sound, owing no doubt to its frequent occurrence in logical and mathematical writings." (Two Dogmas of Empiricism, 1951)

E. V. Rieu:
"That translation is the best which comes neareth to giving its modern audience the same effect as the original had on its first audiences." (Translating the Gospels: A Discussion between Dr. E. V. Rieu and Rev. J. B. Phillips, 1955)

Bertrand Russell:
"In a logically perfect language, there will be one word and no more for every simple object, and everything that is not simple will be expressed by a combination of words, by a combination derived of course, from the words for the simple things that enter in, one word for each simple component." (The Philosophy of Logical Atomism, 1918)

Ernest Rutherford:
"Don't let me catch anyone talking about the universe in my department." (Quoted in J. D. Bernal and the Origin of Life by John Kendrew)

John Searle:
"Well, what does 'good' mean anyway? ... As Wittgenstein suggested, 'good' like 'game has a family of meanings. Prominent among them is this one: 'meets the criteria or standards of assessment or evaluation'." (Speech Acts: An Essay in the Philosophy of Language, 1969)

John Searle:
"You can never understand one language until you understand at least two." (The Storm Over the University, 1990)


Socrates:
"The beginning of wisdom is a definition of terms." (Goodreads.com)

Baruch Spinoza

"A definition, if it is to be called perfect, must explain the inmost essence of a thing, and must take care not to substitute for this any of its properties." (On the Improvement of Understanding, 1622)

Baruch Spinoza:
"My purpose is to explain, not the meaning of words, but the nature of things." (Ethics, 1677

Milton Steinberg:
"It was Thomas Hobbes who anticipating semantics, pointed out that words are counters, not coins; that the wise man looks through them to reality." (Creed of an American Zionist, 1945)

P. F. Strawson:
"There is a massive central core of human thinking which has no history - or none recorded in histories of thought; there are categories and concepts which, in their most fundamental character, change not at all... It is with these, their interconnexions, and the structure that they form, that descriptive metaphysics will be primarily be concerned." (Individuals, 1959)

Voltaire:
"Books, like conversation, rarely give us any precise ideas: nothing is so common as to read and converse unprofitably. We must here repeat what Locke has so strongly urged - Define your terms." (Dictionnaire philosophique, 1764)

Alan Watts:
"The basic problem is to understand that there are no such things as things; that is to say separate things, separate events. That is only a way of talking. What do you mean by a thing? A thing is a noun. A noun isn’t a part of nature it’s a part of speech. There are no nouns in the physical world. There are no separate things in the physical world either." (Quoted in Watts on Wiggles Waves, 2007)

Ludwig Wittgenstein:
"What is the meaning of a word? Let us attack this question by asking first, what is an explanation of the meaning of a word? What does the explanation of a word look like?" (The Blue Book)

Ludwig Wittgenstein:
"What should we gain by a definition, as it can only lead us to other undefined terms?" (The Blue Book, 1965 posthumous)

Ludwig Wittgenstein:
"The idea that in order to get clear about the meaning of a general term one had to find the common element in all its applications has shackled philosophical investigation; for it has not only led to no result, but also made the philosopher dismiss as irrelevant the concrete cases, which alone could have helped him understand the usage of the general term." (The Blue Book, 1965 posthumous)

Ludwig Wittgenstein:
"Uttering a word is like striking a note on the keyboard of imagination." (Philosophical Investigations, 1953 posthumous)

Ludwig Wittgenstein:
"A new word is like a fresh seed sown on the ground of discussion." (Culture and Value, 1980 posthumous)

62. Word use

Henry Ward Beecher:
"Words are pegs to hold on." (The Human Mind, 1887)

Roland Barthes:
"Language is a skin: I rub my language against the other. It is as if I had words instead of fingers, or fingers at the tips of my words. My language trembles with desire." (Talking, 1977)

Benedeto Croce:
"Language is articulated, limited sound organized for the purpose of expression." (Wikiquote)

Carl Eckhart:
"Words and numbers have no existence separate from the people who use them." (Our Modern Idol: Mathematical Science, 1984)

Albert Einstein:
"All concepts, even those which are closest to experience, are from the point of view of logic freely chosen conventions." (Autobiographical notes, 1949)

Ralph Waldo Emerson:
"Language is a city to the building of which every human brought a stone." (Letters and Social Aims,  1876)

Hans-Georg Gadamer:
"The more language is a living operation, the less we are aware of it." (Man and Language, 1966)

Ernst von Glaserfel:
"What we call knowledge does not and cannot have the purpose of producing representations of an independent reality but instead has an adaptive function." (Quoted in Fox, 2001)

Jurgen Habermas:
"Language is not a kind of private property. No one possesses exclusive rights over the common medium of the communicative practices we must intersubjectively share." (The Future of Human Nature, 2003)

Jurgen Habermas:
"I shall develop the thesis that anyone acting communicatively must in performing any speech act, raise universal validity claims and suppose that they can be vindicated." (On the Pragmatics of Communication, 1998)

Aldous Huxley:
"Words are good servants but bad masters." (Quoted in Conversation with Alan Watts)

William James:
"Every way of classifying a thing is but a way of handling it for some particular purpose." (The Sentiment of Rationality, 1882)

Samuel Johnson:
"Every quotation contributes something to the stability or enlargement of the language." (Preface to the Dictionary of the English Language, 1755)

Jacques Lacan:
"The man who is born into existence deals first with language; this is a given. He is even caught in it before his birth." (Interview, 1957)

Maurice Merleau-Ponty:
"Language transcends us and yet we speak." (Phenomenology of Perception, 1945)

Charles Sanders Peirce:
"The definition of definition is at bottom just what the maxim of pragmatism expresses." (Letter to William James, 1909)

Steven Pinker:
"The fact of the matter is that the 'real world' is to a large extent unconsciously built upon the language habits of the group." (Rules of Language, 1991)

John Searle:
"The problem posed by indirect speech acts is the problem of how it is possible for the speaker to say one thing and mean that but also to mean something else." (Expression and Meaning, 1979)

John Searle:
"The assertion fallacy... is the fallacy of confusing the conditions for the performance of the speech act of assertion with the analysis of the meaning of particular words occurring in certain assertions." (Speech Acts: An Essay in the Philosophy of Language, 1969)

Benjamin Whorf:
"We cut nature up, organize it into concepts, and ascribe significances as we do, largely because we are parties to an agreement to organize it in this way." (Language, Thought and Reality, 1956)

Gerald James Witrow:
"Language itself inevitably introduced an element of permanence into the world. For although speech itself is transitiory, the conventionalized sound of symbols of language transcends time." (Wikiquote)

Ludwig Wittgenstein:
"Language is a part of our organism and no less complicated than it." (Notebooks 1914-1916)

Ludwig Wittgenstein:
"An entire mythology is stored within our language." (Philosophical Occasions, 1993 posthumous)

Ludwig Wittgenstein:
"Don't think but look." (Philosophical Investigations, 1953 posthumous)

Ludwig Wittgenstein:
"What we do is to bring words back from their metaphysical to their everyday use." (Philosophical Investigations, 1953 posthumous)