Prisoner's Dilemma

Overview

Whatever the other party does, each player is individually better off defecting — so both defect, and both end up worse than mutual cooperation. This is the structural skeleton beneath price wars, arms races, overfishing, and ad spend spirals. The problem is never character; it is structure. Exhortations to cooperate fail. Change the matrix.

Composes with: second-order-thinking for matrix redesign · expected-value-and-kelly for probabilistic payoffs · repeated-games-reputation for the iterated-game case.

When to Use

• Two or more parties would each do better cooperating, but cooperation keeps failing to materialize
• Situation involves price competition, capacity races, advertising arms races, or commons-style resource depletion
• You are about to negotiate or enter a partnership and want to know whether the structure makes betrayal individually rational
• Someone asks directly about "prisoner's dilemma," "tragedy of the commons," "race to the bottom," or "Nash equilibrium"
• A present-day competitive sprint is in play — an AI capex / compute arms race, AI-safety release race, or AI-native land-grab where every player feels forced to move fast despite preferring collective restraint

When NOT to use: zero-sum games · pure coordination problems (Schelling) · long transparent repeated game with established reputations (use repeated-games-reputation) · low-stakes reversible decisions

Coaching Novices (Adaptive Front Door)