Prisoner's Dilemma
Suppose you and a partner commit burglary. Both of you are picked up by the police who then question you one by one. There is not enough evidence to convict you unless one of you confesses. The interrogator gives you a choice to cooperate or not.
"If you both deny the crime, there is still enough evidence to put you both in jail for 1 year."
"If you both confess, you both go to jail for 3 years."
"If you confess but your partner denies, you will be free and your partner will go to jail for 10 years. "
"If you deny but your partner confesses, you will go to jail for 10 years. "
What should you do? The consequences for you depend on what your partner does. From an outsider's perspective, it seems that both of you would be better off denying the crime (1 year). But from your point of view, it seems best to confess (freedom). The problem is that you don't know what your partner will do. If your partner betrays you, it is better that you also betray him and get 3 years in prison, instead of the 10 years you get if you deny, but your partner ends up confessing. If on the other hand, your partner denies, it is still better that you confess because this way you will be free, instead of the 1 year you get if you deny.
Since both you and your partner follow this "logic" and confess, you will both go to jail for 3 years. Doing what you believe is in your best interest leads to a worse outcome than if you cooperate and deny. But here is the dilemma. You don't know if you can trust your partner. Cooperation only works if you and your partner can trust each other.
✍ Originally Posted: Publish0x