Why is mutual silence better for both prisoners in the prisoner’s dilemma?
The normal-form table illustrates the concept of a saddlepoint, or entry, in a payoff matrix at which the expected gain of each participant (row or column) has the highest guaranteed payoff.
In the prisoner’s dilemma, mutual silence is considered "better" for both prisoners because it results in the most favorable collective outcome. If both prisoners remain silent, they each receive a very light sentence—typically only a few months or one year—which is significantly less time than the five-year sentence each would serve if both confessed.123
However, the dilemma arises because the game is noncooperative and the prisoners cannot make binding agreements. From an individual perspective, each prisoner is tempted to confess to either go free (if the other remains silent) or receive a reduced sentence (if the other also confesses). Because each prisoner acts in their own self-interest without knowing the other's choice, they both end up confessing, which leads to a worse outcome for both than if they had cooperated by remaining silent. This suboptimal result is known as the Nash equilibrium, where neither player can improve their outcome by unilaterally changing their strategy.213