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Louis de Broglie (1892-1987) was a French physicist best known the wave-particle duality theory. Wikipedia says,
"In his 1924 PhD thesis, he postulated the wave nature of electrons and suggested that all matter has wave properties. This concept is known as the de Broglie hypothesis, an example of wave-particle duality, and forms a central part of the theory of quantum mechanics." (Wikipedia: Louis de Broglie, 8.2.21 UTC 11:50)The rest of this post is some quotes from de Broglie.
Scientific progress
"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)
"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 conflict." (Dialectica, 1948)
"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)
"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)
"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)
