The Better Angels of Our Nature: Why Violence Has Declined

Steven Pinker's 2011 synthesis of centuries of data arguing that violence — war, homicide, slavery, ritual cruelty — has declined across every timescale. He traces it through six trends, from the Pacification Process and Civilizing Process to the Long Peace after 1945 and the Rights Revolutions, and explains it through five forces — the Leviathan state, gentle commerce, feminization, cosmopolitanism, and the 'escalator of reason' — alongside a psychology of the better and worse angels of human nature.

Gates calls it "one of the most important books I've read — not just this year, but ever," and credits it with changing how his foundation thinks about strategy: if violence has fallen measurably over centuries, the question becomes what caused the decline and how to accelerate it. That inversion — progress as an explainable, pushable outcome rather than a mystery — is the posture a founder needs toward any problem the world treats as permanent.

The transferable discipline is causal, not sentimental: Pinker doesn't celebrate the decline, he dissects it — which institutions and technologies moved the numbers, and why they could reverse. Any 'it's all getting worse' narrative about your own market deserves the same treatment: decompose it into forces, find the base rate, then decide where to push.