The Evolution of Cooperation

Why it’s on the list: Axelrod ran a tournament of strategies for the iterated prisoner’s dilemma and the winner was the simplest entrant — Tit for Tat: never defect first, retaliate once, forgive immediately. The book generalises from that to trench warfare, biology and trade, and is the foundation text for cooperation as an emergent rather than moral phenomenon.

Where I heard about it

• A crowd-sourced X thread — in the replies to @SpencrGreenberg asking “What non-fiction book taught you the most about how the world (or how humanity or society) really works?” (the thread, June 2025); the full set of replies is on A question for you — What non-fiction… (tweet).
• On Patrick Collison’s Bookshelf — Patrick Collison’s catalog of the physical books he owns (unflagged). Saved in Kyle’s April 19th, 2020 Roam daily note.

Connections

• Robert Axelrod — the author.
• Game Theory — the iterated prisoner’s dilemma as the book’s engine.
• Incentives — why cooperation is stable when the shadow of the future is long enough.
• Darwin’s Blind Spot — the biological version of the same argument, named in the same thread.
• A question for you — What non-fiction… (tweet) — the thread this recommendation came from.