The MANIAC

by Benjamín Labatut

This approach, in which the computer runs through every single possibility arising from each move, is called, appropriately, brute force. While a human player uses memory, experience, high-level abstract reasoning, pattern recognition, and intuition to cast his or her mind over the board, a chess engine does not really understand the game at all, it simply uses its power to calculate and then makes a decision following a complex set of hand-crafted rules laid down by its programmers. Each time its opponent places a piece on a black or white square, the computer constructs a search tree consisting of every possible future arising from that particular configuration of the board; the tree keeps on growing and branching out till it reaches the end of the game, and the computer simply selects between its many limbs the outcomes that it considers most advantageous. With each new move comes a different tree, as the game changes and evolves constantly, but with enough power, the computer can look so far into the future as to remain a step, if not several thousand steps, ahead of any human opponent.