What is The Better Angels of Our Nature about?

The Better Angels of Our Nature is Steven Pinker's argument, supported by extensive historical and statistical data, that human violence has declined dramatically over long time periods and that this decline is real, not an artifact of reporting or perception. The thesis is counterintuitive: most people believe the twentieth century was the most violent in history, and most people believe the world is getting more violent. Pinker argues both beliefs are wrong.

The case is built in layers. Prehistoric and early historical societies were substantially more violent than modern ones: archaeological evidence of interpersonal violence, combined with ethnographic data from hunter-gatherer and tribal societies, suggests that several percent of all deaths in pre-state societies were caused by other people. State formation reduced that rate dramatically by creating monopolies on force and systems of deterrence. Medieval European homicide rates were ten to fifty times higher than modern ones. Judicial torture was routine; public execution was entertainment. The decline of these practices was real and measurable.

Pinker identifies several forces behind the long decline: the pacifying effect of states and trade, the feminization of culture, the expansion of literacy and the imagination of other people's inner lives, the rise of reason and Enlightenment norms, and specific international institutions and norms that emerged after World War II. The data on interstate wars, civil wars, genocides, and homicides all show declines, though with significant variation by region and time period.

The book also examines the inner demons and better angels of the title: the psychological motives that drive violence (dominance, revenge, ideology, sadism) and the capacities that suppress it (empathy, self-control, moral reasoning, cosmopolitanism). This is where Pinker's evolutionary psychology and his historical argument connect: the same psychological equipment produces different outcomes depending on the institutions and norms it operates within.

The thesis has been contested. Critics argue that the data undercount certain kinds of violence, that the twentieth century's absolute death totals require more weight than per-capita statistics give them, and that existing peace may be fragile rather than structural. Pinker addresses many of these objections in the book, though debates continue.