Gettier

Edmund L. Gettier III (born October 31, 1927 in Baltimore, Maryland) is an American philosopher and Professor Emeritus at the University of Massachusetts Amherst. He is best known for his short 1963 paper, "Is Justified True Belief Knowledge?," which generated an extensive philosophical literature trying to respond to what became known as the Gettier problem.

Gettier was educated at Cornell University, where his mentors included Max Black and Norman Malcolm. Gettier, himself, was originally attracted to the opinions of the later Ludwig Wittgenstein. His first teaching job was at Wayne State University in Detroit, Michigan, where his colleagues included Keith Lehrer, R. C. Sleigh, and Alvin Plantinga. Because he had few publications, his colleagues urged him to publish any ideas he had just to satisfy the administration. The result was a three-page paper that remains one of the most famous in recent philosophical history. According to anecdotal comments that Plantinga has given in lectures, Gettier was originally so unenthusiastic about the paper that he had someone translate it into Spanish, and published it first in a South American journal. The paper was later published in Analysis. Gettier has since not published anything, but he has invented and taught to his graduate students new methods for finding and illustrating countermodels in modal logic, as well as simplified semantics for various modal logics.

In his article, Gettier challenges the "justified true belief" definition of knowledge that dates back to Plato's Theaetetus, but is discounted at the end of that very dialogue. This account was accepted by most philosophers at the time, most prominently the epistemologist Clarence Irving Lewis and his student, Roderick Chisholm. Gettier's article offered counter-examples to this account in the form of cases such that subjects had true beliefs that were also justified, but for which the beliefs were true for reasons unrelated to the justification. Some philosophers, however, thought the account of knowledge as justified true belief had already been questioned in a general way by the work of Wittgenstein. (Later, a similar argument was found in the papers of Bertrand Russell).

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