there is a kind of liberal triumphalism that sometimes traces progress simply to moral enlightenment—to the gradual triumph of better ideas over worse ones. Although there is an important grain of truth here—many societies really have become more rational, humane, and tolerant—the existence of factory farming, among other ongoing atrocities, complicates any simple story of moral progress. Instead of becoming better people, we have built better systems of norms and institutions for channelling the same flawed human nature towards less catastrophic outcomes, at least for other humans.