The Dilemma of the Prisoners' Dilemmas

This paper distinguishes four types of 'Prisoners' Dilemma games - provision, the commons, selfishness, and altruism - based on the public character of benefits and costs. Although each of these four games has the same 2 x 2 ordinal game form, each differs in terms of strategic, dynamic, and policy implications. Similar differences characterize the n-person representations of the four games. When paired in 3 x 3 representations, the least-desirable Nash equilibrium of the two embedded 2 x 2 games results. The four types of PD games also have different evolutionary and informational requirements for cooperation. Applications include the environment, biology, counterterrorism, and international relations