Ian Hacking is a Canadian theorist of science and philosopher of language. Since 1982 he was professor at the University of Toronto, and from 2001 to 2006 honorary professor of philosophy and history of scientific concepts at the Collège de France. Within the philosophy of science, Hacking, together with Nancy Cartwright, John Dupre and Patrick Suppes, belongs to the Stanford school, which is united by the critical approach to the reductionist ideal of unified science.