Introduction to Prisoners' Dilemma

The game-theory sequence's intro to the Prisoner's Dilemma: the Alice/Bob setup, why defection dominates each branch, and the intuitive wrongness that both prefer (cooperate, cooperate) to (defect, defect) yet land on the latter — sharpened by the variant where cooperation would cost a day and defection nineteen years, and the math still says defect. Then iterating with reciprocation (cooperate now to be rewarded later), and the backward-induction unraveling: defection on the known last crime propagates by induction back to defection on all of them. Notes this rarely bites in real life, where crime-spree lengths are uncertain, and promises solutions next post.

Quality 68 · Strong. Upper-Solid. A clean, correct textbook introduction with a couple of nice intuition pumps, but pure exposition with no original thesis (it is the sequence's setup post), so it sits with the primers.

Claude’s paradigm shift 30 · Slight. Slight — standard Prisoner's Dilemma and backward induction; pedagogical, not novel.

Real-world impact 2 · Minor. A clean textbook introduction to the Prisoner's Dilemma (the sequence's setup post); pedagogical reach within the community, no original thesis or material reach → RWI 2.