This article examines the most prominent interwar economist at the University of Chicago, Frank Knight, through the lens of a controversial 1932 lecture in which he exhorted his audience to vote Communist. The fact that he did so poses a historical problem: why did the premier American exponent of conservative economic principles appear to advocate a vote for radical change? This article argues that the speech is representative of Knight's deliberately paradoxical approach, in which he refused to praise markets without (...) adding caveats about their substantial limitations, and expressed support for freedom of discussion alongside his skepticism of the public's capacity to exercise the privilege. In parsing these tensions, the article revises the conventional interpretation of Knight, illuminates the contested environment within which postwar free-market economics emerged, and reexamines a restrained defense of capitalism that has been largely forgotten in the subsequent years. (shrink)