On the History of the Idea of Law traces the development of the philosophical theory of law from its first appearance in Plato's writings to today. Shirley Letwin finds important and positive insights and tensions in the theories of Plato, Aristotle, Augustine, and Hobbes as well as confusion and serious errors introduced by Cicero, Aquinas, Bentham, and Marx. She harnesses the insights of H.L.A. Hart and especially Michael Oakeshott to mount a devastating attack on the late twentieth-century theories of Ronald Dworkin, the Critical Legal Studies movement, and feminist jurisprudence.