In its iterated form, successful strategies tend to be nice, (*) retaliating, forgiving, and non-envious, making tit-for-tat one of the best deterministic algorithms.
Hardin's tragedy of the commons is sometimes said to be an example of a multi-player generalization of it. It demonstrates that in a non-zero-sum game, the Nash equilibrium isn't necessarily Pareto optimal. In its iterated form, successful strategies tend to be nice, (*) retaliating, forgiving, and non-envious, making tit-for-tat one of the best deterministic algorithms. In its payoff matrix as described by Douglas Hofstadter, the sucker's payoff must have the lowest value and the temptation to defect payoff must have the highest value. FTP, name this game in which each of two players can choose to either cooperate or defect.
Hardin's tragedy of the commons is sometimes said to be an example of a multi-player generalization of it.
{prisoner's dilemma}