Friedrich August Hayek (1899–1992), recipient of the Medal of Freedom in 1991 and co-winner of the Nobel Memorial Prize in Economics in 1974, was a pioneer in monetary theory and the principal proponent of libertarianism in the twentieth century. He taught at the University of London, the University of Chicago, and the University of Freiburg. His influence on the economic policies in capitalist countries has been profound, especially during the Reagan administration in the U.S. and the Thatcher government in the U.K.