Because the game requires logical reasoning, chess would seem to be perfectly suited to the computer. All a programmer has to do is give the computer a program evaluating the consequences of every possible response to every possible move, and the computer will win every time. In theory this is a sensible approach; in practice it is impossible. Today, a powerful computer can analyze 40000 moves a second. That is an impressive speed. But there are an astronomical number of possible moves in chess—literally trillions. Even if such a program were written, there is no computer capable of holding that much data. Therefore, if the computer is to compete at championship levels, it must be programmed to function with less than complete data. It must be able to learn from experience, to modify its own program, to deal with a relatively unstructured situation—in a word, to “think” for itself . In fact, this can be done.