As quotes go, it’s notable: “Politics is not a dinner party.” I harbor no great fondness for Mao Zedong, but I do think that his famed comment points to a provocative truth about politics. Liberals and centrists today often act tacitly as if political ethics and personal ethics are identical. The “Would you have a beer with them?” test for presidential candidates commonly employed by pundits reinforces this unity. But our codes of individual and interpersonal ethics—the virtues we strive to cultivate in ourselves as people and how we behave with friends, family, and acquaintances—necessarily differ from public, political ethics, as theorists stretching back to Plato and Aristotle have recognized.