Yuval Levin traces the origins of America's left-right political divide to the intellectual confrontation between Edmund Burke and Thomas Paine during the French Revolution. Though both began as critics of British policy, Burke responded to the revolution with horror at its abstract rationalism and destruction of inherited institutions, while Paine celebrated its attempt to rebuild society on rational principles. Levin reads their major works closely, showing how Burke's defense of tradition, prejudice, and gradual reform generated a conservatism that seeks to preserve what works, while Paine's faith in reason, natural rights, and the possibility of starting over generated a progressivism that seeks to restore what society has corrupted. The book argues that both positions contain insights and blindnesses: Burke underestimates how tradition can calcify injustice, while Paine underestimates how radical change produces unintended consequences. Levin, a conservative intellectual who has written sympathetically about both government programs and traditional institutions, uses the historical analysis to illuminate contemporary debates. He suggests that healthy politics requires both sensibilities—the reforming conservatism that improves institutions incrementally and the restoring progressivism that reminds us what principles those institutions should serve. Readers across the political spectrum will find their own positions clarified by encounter with their intellectual origins, and may discover that Burke and Paine, for all their opposition, share more with each other than with the ideological certainties of the present moment.