David Director Friedman (born February 12, 1945) is an American economist, physicist, legal scholar, and anarcho-capitalist theorist. Although his academic training was in chemistry and physics and not law or economics, he is known for his textbook writings on microeconomics and the libertarian theory of anarcho-capitalism, which is the subject of his most popular book, The Machinery of Freedom. Described by Walter Block as a "free-market anarchist" theorist, Friedman has also authored several other books and articles, including Price Theory: An Intermediate Text (1986), Law's Order: What Economics Has to Do with Law and Why It Matters (2000), Hidden Order: The Economics of Everyday Life (1996), and Future Imperfect (2008). Source: Wikipedia (en)