Milton Friedman (1912 - 2006)  
He was an American Nobel Laureate economist and public intellectual. An advocate of laissez-faire capitalism, Friedman made major contributions to the fields of macroeconomics, microeconomics, economic history and statistics. In 1976, he was awarded the Nobel Prize in Economics for his achievements in the fields of consumption analysis, monetary history and theory and for his demonstration of the complexity of stabilization policy.
According to The Economist, Friedman "was the most influential economist of the second half of the 20th century… possibly of all of it".
Alan Greenspan stated "There are very few people over the generations who have ideas that are sufficiently original to materially alter the direction of civilization. Milton is one of those very few people".
In his 1962 book Capitalism and Freedom, Friedman advocated minimizing the role of government in a free market as a means of creating political and social freedom. In his 1980 television series Free to Choose Friedman explained how the free market works, emphasizing that its principles have been shown to solve social and political problems that other systems have failed to address adequately. His books and columns for Newsweek were widely read and even circulated underground behind the Iron Curtain.
Earning a Ph.D in economics from Columbia University in 1946, Friedman originally was a Keynesian supporter of the New Deal and advocate of high taxes. However he moved to the right in the 1950s, along with his close friend George Stigler. Before the 1970s their advocacy of free markets was a minority view among economists. His political philosophy, which Friedman himself considered classically liberal and consequentialist libertarian, stressed the advantages of the marketplace and the disadvantages of government intervention, shaping the outlook of American conservatives and libertarians. He adamantly argued that if capitalism, or economic freedom, is introduced into countries governed by totalitarian regimes that political freedom would tend to result. He lived to see his laissez-faire ideas embraced by the mainstream, especially during the 1980s, a watershed decade for the acceptance of Friedman's ideas. His views of monetary policy, taxation, privatization and deregulation informed the policy of governments around the globe, especially the administrations of Ronald Reagan in the U.S. and Margaret Thatcher in Britain.
Friedman's political positions were buttressed by a large number of technical articles covering a wide range of topics in economics and economic history, which gained the grudging respect of specialists by the early 1960s. His intellectual leadership of the Chicago School, which came to dominate theoretical economics by the 1970s, further strengthened his stature.

(Source: Wikipedia)