 Suppose first that the agents have common knowledge of the full payoff structure of the game they are engaged in and that they are all rational, and that no other information is common knowledge. In other words, each agent knows that her opponents are expected utility maximizers, but does not in general know exactly which strategies they will choose or what their probabilities for her acts are. These common knowledge assumptions are the motivational basis for the solution concept for noncooperative games known as rationalizability, introduced independently by Bernheim (1984) and Pearce (1984). Roughly speaking, a rationalizable strategy is any strategy an agent may choose without violating common knowledge of Bayesian rationality. Bernheim and Pearce argue that when only the structure of the game and the agents’ Bayesian rationality are common knowledge, the game should be considered “solved” if every agent plays a rationalizable strategy. For instance, in the “Chicken” game with payoff structure defined by Figure 3.1,