US economist Milton Friedman, whose theories on macro-economics greatly influenced former prime minister Margaret Thatcher and US presidents has died at the age of 94.
The winner of the 1976 Nobel prize for economics died in San Francisco following heart failure, his family confirmed.
Born on July 31st 1912 in Brooklyn, the son of Austro-Hungarian Jewish immigrants went from humble beginnings to become one of the most influential economists in the latter half of the 20th century.
His espousal of free market economies and a laissez faire attitude from government held sway over Lady Thatcher and her contemporary in the White House Ronald Reagan, with the professor of economics at the University of Chicago championing both deregulation and privatisation.
"Milton Friedman revived the economics of liberty, when it had been all but forgotten," said the former prime minister last night.
"He was an intellectual freedom fighter. Never was there a less dismal practitioner of 'the dismal science'. I shall greatly miss my old friend's lucid wisdom and mordant humour."
Mr Friedman strongly asserted that the flow of money was the most important factor in ensuring economic growth and maintaining inflation.
He also famously coined the phrase "there's no such thing as a free lunch".
Gordon Brown has described the American as one of the "great economic theorists", with the chancellor adding: "He had a major influence on post-war economic policy not least in establishing the importance of credibility in monetary policy making."
The president of the Milton Friedman Foundation last night said that "America has lost a true visionary and advocate for human freedom; and I have lost a great friend".
Gordon St Angelo went on to say: "Milton's passion for freedom and liberty has influenced more lives than he ever could possibly know. His writings and ideas have transformed the minds of US presidents, world leaders, entrepreneurs and freshmen economic majors alike. The loss of his passion, incisive mind and dedication to freedom are all national treasures that we mourn for today.
"His impact on my life over the last 33 years was significant. His impact on the world was momentous. Without a doubt, few people have done more to advance civil and economic liberties throughout the world during their lifetime than Dr Milton Friedman."