Always Play to Win
When playing white, Fischer have always played aggressively by controlling the center. It gave him the one move advantage. His next strategic step was to target his attention toward the location of the challenger's king. Strategically, his grand objective was to force the challenger to play catch up throughout the game.
As black, Fischer chose aggressive defenses. By constantly matching the opposition's move with an incremental set of counter-offensive moves, the weaker opposition would somehow err. Early control of the tempo and the space of the game board enabled him to frequently forced the opposition into play his game.
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