Prisoner's Dilemma¶
Summary¶
A game theory scenario where two individuals would be better off cooperating, but each has an incentive to defect — leading to a worse outcome for both when both defect.
The Payoff Matrix¶
| B Cooperates | B Defects | |
|---|---|---|
| A Cooperates | Both get 3 points | A: 0, B: 5 |
| A Defects | A: 5, B: 0 | Both get 1 point |
Rational choice (one-off): Always defect (weakly dominant strategy) Rational choice (repeated): Cooperate first, then copy opponent (Tit for Tat)
Real-World Examples¶
- Roommate dish duty
- Price wars between businesses
- Nuclear arms races
- Climate change cooperation