Bastiaan Cornelis "Bas" van Fraassen (; ; born 5 April 1941) is a Dutch-American philosopher noted for his contributions to philosophy of science, epistemology and formal logic. He is a Distinguished Professor of Philosophy at San Francisco State University and the McCosh Professor of Philosophy Emeritus at Princeton University.
Biography and career
Van Fraassen was born in the German-occupied Netherlands on 5 April 1941. His father, a steam fitter, was forced by the Nazis to work in a factory in Hamburg. After the war, the family reunited and, in 1956, emigrated to Edmonton, in western Canada.
Van Fraassen earned his B.A. (1963) from the University of Alberta and his M.A. (1964) and Ph.D. (1966, under the direction of Adolf Grünbaum) from the University of Pittsburgh. He previously taught at Yale University, the University of Southern California, the University of Toronto and, from 1982 to 2008, at Princeton University, where he is now emeritus.
Van Fraassen is an adult convert to the Roman Catholic Church and is one of the founders of the Kira Institute. He is a fellow of the American Academy of Arts and Sciences; an overseas member of the Royal Netherlands Academy of Arts and Sciences since 1995; and a member of the International Academy of Philosophy of Science. In 1986, Van Fraassen received the Lakatos Award for his contributions to the philosophy of science and, in 2012, the Philosophy of Science Association's inaugural Hempel Award for lifetime achievement in philosophy of science. In 2026, he was awarded the Rolf Schock Prize in Logic and Philosophy.
Among his many students are the philosophers Elisabeth Lloyd at Indiana University, Anja Jauernig at New York University, Jenann Ismael at Johns Hopkins University, Ned Hall at Harvard University, Alan Hajek at the Australian National University and Professor of Mathematics Jukka Keranen at UCLA.
Philosophical work
Philosophy of science
Van Fraassen coined the term "constructive empiricism" in his 1980 book The Scientific Image, in which he argued for agnosticism about the reality of unobservable entities. That book was "widely credited with rehabilitating scientific anti-realism." According to the Stanford Encyclopedia of Philosophy: