Photo source: Wikimedia Commons, Oursipan
Saul Kripke (1940-now) is an American philosopher best known for his contributions to the philosophy of language, modal logic and establishing Kripke semantics. Kripke is also known for his book Wittgenstein on Rules and Private Language (1982) which is an analysis of Ludwig Wittgenstein's book Philosophical Investigations (1953, posthumous). Wikipedia says,
"Since the 1960's Kripke has been a central figure in a number of fields related to mathematical logic, philosophy of language, philosophy of mathematics, metaphysics, epistemology, and set theory." (Wikipedia: Saul Kripke, 8.20.21 UTC 21:30)The rest of this post is some quotes from Kripke.
Names
"Let's call something a rigid designator if in every possible world it designates the same object..." (AZquotes.com)
"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)
Logic
"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)
Truth
"Any necessary truth, whether a priori or a posteriori, could nit have turned out otherwise." (AZquotes.com)