Saul Kripke

Saul Kripke
Kripke in 2005
Born	(1940-11-13)November 13, 1940 Bay Shore, New York, U.S.
Died	September 15, 2022(2022-09-15) (aged 81) Plainsboro, New Jersey, U.S.
Education	Harvard University (B.A., 1962)
Awards	Rolf Schock Prizes in Logic and Philosophy (2001)
Era	Contemporary philosophy
Region	Western philosophy
School	Analytic
Institutions	Princeton University CUNY Graduate Center
Main interests	Logic (particularly modal) Philosophy of language Metaphysics Set theory Epistemology Philosophy of mind History of analytic philosophy
Notable ideas	List Kripke–Platek set theory Work on theory of reference (causal theory of reference, causal-historical theory of reference,[1] direct reference theory, criticism of the Frege–Russell view) Admissible ordinal Kripke structure Rigid vs. flaccid designator A posteriori necessity The possibility of analytic a posteriori judgments[2][3] Semantic theory of truth (Kripke's theory) Non-analytic, a posteriori necessary truths[4] Contingent a priori[5] Kripke semantics Disquotational principle Accessibility relation Rule-following paradox (Kripkenstein) Humphrey objection

Saul Aaron Kripke (/ˈkrɪpki/; November 13, 1940 – September 15, 2022) was an American analytic philosopher and logician. He was Distinguished Professor of Philosophy at the Graduate Center of the City University of New York and emeritus professor at Princeton University. Kripke is considered one of the most important philosophers of the latter half of the 20th century.^[6] Since the 1960s, he has been a central figure in a number of fields related to mathematical and modal logic, philosophy of language and mathematics, metaphysics, epistemology, and recursion theory.

Kripke made influential and original contributions to logic, especially modal logic. His principal contribution is a semantics for modal logic involving possible worlds, now called Kripke semantics.^[7] He received the 2001 Schock Prize in Logic and Philosophy.

Kripke was also partly responsible for the revival of metaphysics and essentialism after the decline of logical positivism, claiming necessity is a metaphysical notion distinct from the epistemic notion of a priori, and that there are necessary truths that are known a posteriori, such as that water is H₂O. A 1970 Princeton lecture series, published in book form in 1980 as Naming and Necessity, is considered one of the most important philosophical works of the 20th century. It introduces the concept of names as rigid designators, designating (picking out, denoting, referring to) the same object in every possible world, as contrasted with descriptions. It also contains Kripke's causal theory of reference, disputing the descriptivist theory found in Gottlob Frege's concept of sense and Bertrand Russell's theory of descriptions. Kripke is often seen in opposition to the other great late-20th-century philosopher to eschew logical positivism: W. V. O. Quine. Quine rejected essentialism and modal logic.^[8][9]

Kripke also gave an original reading of Ludwig Wittgenstein, known as "Kripkenstein", in his Wittgenstein on Rules and Private Language. The book contains his rule-following argument, a paradox for skepticism about meaning. Much of his work remains unpublished or exists only as tape recordings and privately circulated manuscripts.