Robert Nozick, in chapter two of the nature of rationality, proposes two famous problems in decision theory (i.e., Newcomb's problem and Prisoner Dilemma) and two main strategies toward these problems i.e. dominant strategy and dominated or cooperative one. He will try to give a formal principles to calculate the decision values in these situations. In this calculation he goes beyond the standard principle of maximizing expected utility and would try to put forth less ideal and more realistic principles that fit (...) the decision situation in the real world. (shrink)

David Gauthier in his article, Maximization constrained: the rationality of cooperation, tries to defend of the joint strategy in situations which no outcome is both equilibrium and optimal. Prisoner’s Dilemma is the most familiar example of these situations. He first starts with some quotes by Hobbes in Leviathan; Hobbes, in chapter 15 discusses an objection by someone is called Foole, and then will reject his view. In response to Foole, Hobbes presents two strategies (i.e. joint and individual) and two kinds (...) of agents in such problems including Prisoner’s Dilemma – i.e. straightforward maximizer (SM) and constrained maximizer(CM). Then he considers two arguments respectively for SM and CM, and he will show that why in an ideal and transparent situation, the first argument fails and the second one would be the only valid argument. likewise, in the following part of his article, he considers more realistic situations with translucency and he concludes that under some conditions, joint strategy would be still the rational decision. (shrink)