The Prisoner's Dilemma: Why Cooperation is Hard
The Prisoner's Dilemma is one of the most famous examples in game theory. Two prisoners are separately interrogated. If both stay silent, they each serve 1 year. If one betrays while the other stays silent, the betrayer goes free while the other serves 3 years. If both betray, they each serve 2 years.
The paradox? Rational self-interest leads both to betray, resulting in a worse outcome (2 years each) than if they had cooperated (1 year each). This demonstrates how individual rationality can lead to collective irrationality.
Key Insight:
The Nash equilibrium (both betray) is not Pareto optimal. This applies to real-world scenarios like arms races, environmental protection, and business competition.