Counterintuitive Facts (14): How Did Kindness Survive in This Cold Universe?

I. In the classic Prisoner's Dilemma, the rational choice is always to defect. Two prisoners are interrogated separately. If both stay silent (cooperate), each gets 1 year. If both confess (defect), each gets 5 years. If one confesses and one doesn't, the confessor goes free, the silent one gets 10 years.

II. No matter what the other person chooses, defecting always gives me higher payoff.

• If they cooperate, I defect: I go free (best outcome)
• If they defect, I defect: I get 5 years (better than 10) So defection is the dominant strategy.

III. But if both think this way, both defect, both get 5 years. When mutual cooperation would only mean 1 year each. A much better outcome. But rationality led them to the inferior result. Kindness is the enemy of rationality.

IV. This conclusion is despa