During the past three centuries, three economists stand out as archetypes, symbols of three distinct approaches to economic philosophy. In the eighteenth century, Adam Smith, a student of the Scottish Enlighten-ment, expounded a “system of natural liberty” (what we might term a liberal democratic order consisting of an unfettered market and limited government), and elucidated how a nation flourishes and advances the standard of living of its citizens. In the nineteenth century, the German philosopher Karl Marx attracted and inspired workers and intellectuals who felt disenfranchised by industrial capitalism and sought radical solutions to inequality, alienation, and exploitation of the underprivileged. Finally, in the twentieth century, the British economist John Maynard Keynes sought to stabilize a crisis-prone market system through activist fiscal and monetary government policies.