John Kenneth "Ken" Galbraith, OC (October 15, 1908 April 29, 2006) was a Canadian-American economist. He was a Keynesian and an institutionalist, a leading proponent of 20th-century American liberalism and progressivism. His books on economic topics were bestsellers from the 1950s through the 1970s and he filled the role of public intellectual in this period on matters of economics. Galbraith was a prolific author who produced four dozen books and over a thousand articles on various subjects. Among his most famous works was a popular trilogy on economics, American Capitalism (1952), The Affluent Society (1958), and The New Industrial State (1967). He taught at Harvard University for many years. Galbraith was active in politics, serving in the administrations of Franklin D. Roosevelt, Harry S. Truman, John F. Kennedy and Lyndon B. Johnson; and among other roles served as United States Ambassador to India under Kennedy. He was one of the few honorees who received the Presidential Medal of Freedom twice.