This is the first draft of a chapter in a planned book on the Prisoner's Dilemma, edited by Martin Peterson, to be published by Cambridge University Press. It discusses the nature of the conditionals involved in deliberation, taking the Prisoner's Dilemma game as point of departure. --...

In [5] (Int. J. Game Theory, 42:567-592, 2013) a general notion of perfect Bayesian equilibrium (PBE) was introduced for extensive-form games and shown to be intermediate between subgame-perfect equilibrium and sequential equilibrium. The essential ingredient of the proposed notion is the...