Equilibrium Outcomes of Repeated Two-Person, Zero-Sum Games

We consider repeated two-person, zero-sum games in which the preferences in the repeated game depend on the stage-game preferences, although not necessarily in a time-consistent way. We assume that each player's repeated game payoff function at each period of time is strictly increasing on the stage game payoffs and that the repeated game is itself a zero-sum game in every period. Under these assumptions, we show that an outcome is a subgame perfect outcome if and only if all its components are Nash equilibria of the stage game.