The essence of the problem is neatly captured by a scenario known as the Prisoners’ Dilemma, which was originally developed in the branch of mathematics called game theory. Two prisoners are being held in separate rooms, goes the story, and the police are interrogating both of them about a crime they committed jointly. Each prisoner has a choice: he can inform on his partner (“defect”) or else remain silent (“cooperate”—with his partner, not the police).
