War has been with us ever since the dawn of civilization. Nothing has been more constant in history than war.
Robert AumannThe strong equilibrium point f just described is one of "unrelenting ferocity" against offenders. It exhibits a zeal for meting out justice that is entirely oblivious to the sometimes dire consequences to oneself or to the other faitheful i.e., those who have not deviated.
Robert AumannRepetition acts as an enforcement mechanism: It makes cooperation achievable when it is not achievable in the one-shot game, even when one replaces strategic equilibrium as the criterion for achievability by the more stringent requirement of perfect equilibrium.
Robert Aumann