John Buridan (ca. 1300-1361) was the most famous philosophy teacher of his time, and probably the most influential. In this important new book, Jack Zupko offers the first systematic exposition of Buridan's thought to appear in any language. Zupko uses Buridan's own conception of the order and practice of philosophy to depict the most salient features of his thought, beginning with his views on the nature of language and logic and then illustrating their application to a series of topics in metaphysics, natural philosophy, and ethics.