Kenneth Jon Barwise (June 29, 1942 - March 5, 2000) was a U.S. mathematician, philosopher and logician who proposed some fundamental revisions to the way that logic is understood and used.
Born Independence, Missouri to Kenneth T. and Evelyn, he was a precocious child.
A pupil of Solomon Feferman at Stanford University, Barwise started his research in infinitary logic. After positions as assistant professor at the Universities of Yale and Wisconsin, during which time his interests turned to natural language, he returned to Stanford in 1983 to direct the Center for the Study of Language and Information. He began teaching at Indiana University in 1990.
Barwise contended that, by being explicit about the context in which a proposition is made, the situation, many problems in the application of logic can be eliminated. He sought ... to understand meaning and inference within a general theory of information, one that takes us outside the realm of sentences and relations between sentences of any language, natural or formal. In particular, he claimed that such an approach resolved the liar paradox. He made use of Peter Aczel's non-well-founded set theory in understanding "vicious circles" of reasoning.
Barwise, along with his former colleague at Stanford John Etchemendy, was the author of the popular logic textbook Language, Proof and Logic. The text is notable for including computer-aided homework problems, some of which provide visual representations of logical problems.
He was diagnosed with colon cancer in 1999 and throughout the rest of his life made an exhaustive exploration of his condition both through conventional and alternative medicine, and by articulating his own emotional experience. The Ting-sha Institute in Inverness, California played an important part in his journey. Indiana University's School of Informatics has named a scholarship for Master's degree students in his honor.