Prisoner's Dilemma

Police station, 2:14 a.m. You and your partner, Kim — three years working side by side — are in separate interrogation rooms, a single wall between you. You cannot hear each other. A detective slides a sheet of paper across your table. 'Simple. Both stay silent: one year each. Both confess: five years each. You confess, Kim doesn't: you walk, Kim gets ten years. He confesses, you don't: the reverse.' He glances at his watch. 'Kim is hearing the same offer right now. Thirty minutes to decide.' You think of Kim — three years together, and he has never betrayed you. But he is staring at the same paper, watching the same clock, and the same thirty minutes are passing for him too. Will he hold? Or talk? His decision controls ten years of your life, and yours controls ten of his.