How this instrument works
The Prisoner's Dilemma is a classic scenario in game theory built around a fixed payoff matrix with four named outcomes: Reward (both players cooperate), Temptation (you defect while the other cooperates), Sucker's payoff (you cooperate while the other defects), and Punishment (both defect). This page uses the standard textbook values: Reward=3, Temptation=5, Sucker's payoff=0, Punishment=1.
The dilemma itself is that mutual cooperation gives the best outcome for the GROUP (a combined payoff of 6, three each) — yet each individual player is always personally better off defecting, regardless of what the other player does: defecting turns a Sucker's payoff of 0 into a Punishment of 1, and turns a Reward of 3 into a Temptation of 5. That individual incentive to defect is exactly what can drag both players down to mutual Punishment, even though mutual cooperation was available and better for both.
This tension shows up well beyond literal prisoners — pricing wars between competing businesses, arms races between nations, and shared-resource problems all share the identical payoff structure, which is why the scenario has become a standard reference point across economics, biology, and political science.
- Set Player 1's choice to cooperate (1) or defect (0).
- Set Player 2's choice the same way.
- Read Player 1's payoff and Player 2's payoff for that specific combination.
- Try all four combinations to see the complete payoff matrix and confirm each player is individually better off defecting no matter what the other chooses.
Worked example — three outcomes compared
If both players cooperate: each gets the Reward payoff, 3 — the best MUTUAL outcome, six points combined, though not the best outcome available to either player individually, which is exactly what makes the dilemma a dilemma in the first place.
If player 1 cooperates while player 2 defects: player 1 gets the Sucker's payoff, 0, while player 2 gets the Temptation payoff, 5 — the single best individual result, available only by defecting against a cooperating opponent. If both players defect instead: each gets the Punishment payoff, 1 — worse for both than mutual cooperation would have been, yet defecting remains each player's individually safer choice regardless of the other's decision.
Questions
What is the Prisoner's Dilemma?
A game-theory scenario where two players each choose to cooperate or defect, under a fixed payoff structure where mutual cooperation gives the best GROUP outcome, but each player is individually always better off defecting no matter what the other chooses.
Why would anyone defect if cooperating gives a better combined outcome?
Because defecting is always the individually safer choice regardless of the other player's decision — it turns a Sucker's payoff of 0 into a Punishment of 1, and a Reward of 3 into a Temptation of 5, an improvement either way, even though both players defecting together leaves both worse off than mutual cooperation would have.
What are the four payoff outcomes called?
Reward (mutual cooperation, 3), Temptation (defecting against a cooperator, 5), Sucker's payoff (cooperating against a defector, 0), and Punishment (mutual defection, 1) — the standard textbook values used throughout this page.
Where does the Prisoner's Dilemma show up outside literal prisoners?
Pricing competition between businesses, arms races between nations, and shared-resource problems all share the identical payoff structure, which is why the scenario is used as a standard reference point well beyond its original framing.
Is there a way to guarantee mutual cooperation?
Not within a single, one-off round under this payoff structure — repeated play, reputation, or outside enforcement can shift the incentives, but a single isolated round always leaves defection as the individually dominant choice for both players.