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OK, you should all know who he is; after all, most of the current U.S. monetary policy is based on his theories. He was a steadfast supporter of limited government and laissez-faire capitalism, which (somewhat unfortunately) helped to create the modern Libertarian politics championed by countless Internet trolls. Which of course was not his fault--like so many other economic and political theorists, his ideas were dumbed down and misapplied by people far less talented than himself (e.g., most politicians).
Regardless of whether you agree with his ideas, he was massively influential and certainly will be missed.