Joseph Raz (/rɑːz/; Hebrew: יוסף רז; born 21 March 1939) is an Israeli legal, moral and political philosopher. He is one of the most prominent advocates of legal positivism and is well known for his conception of perfectionist liberalism. Raz spent most of his career as a professor of philosophy of law at the University of Oxford associated with Balliol College, and is now a part-time professor of law at Columbia University Law School and a part-time professor at King's College London.