For 10 points  identify this fundamental theorem of game theory, developed by John von Newmann.
In a zero-sum game, a rational player will hedge his bets by choosing a strategy that gives his opponent the worst best-possible outcome.  The other player, knowing that the first player is acting rationally, will expect him to play the strategy just described and so will choose the one responding strategy that gives him the best outcome under that scenario.  As a result, every finite, two-person, zero-sum game has a single outcome that can be predicted with certainty if both players are rational.  For 10 points  identify this fundamental theorem of game theory, developed by John von Newmann.
In a zero-sum game, a rational player will hedge his bets by choosing a strategy that gives his opponent the worst best-possible outcome.  
The Minimax Theorem