Computers don't tire, crack under time pressure, or get psyched out--and that makes them formidable chess players. In Bahrain last week, world champion Vladimir Kramnik and chess computer Deep Fritz drew the final game of their eight-game series, and the "Brains in Bahrain" match was declared a tie. But it was a substantial victory for the creators of Deep Fritz, who proved that computers can match the abilities of even the best human chess players.
In 1997, then-champion Garry Kasparov lost a six-game match to IBM's improved Deep Blue computer, but many chess aficionados (including Kasparov) argued that the tournament was unfair. For instance, Kasparov wasn't given the opportunity to learn about his opponent, says Frederic Friedel of Hamburg-based ChessBase and one of the people behind the Deep Fritz program. Friedel and colleagues allowed Kramnik to play with the program for 3 months.
At heart, Deep Fritz is very much like other advanced chess computers; it has a vast database of openings and endings, and it relies on brute force--with some fine-tunings--to go through all possible moves and decide on the best line to play. After the first game, which was a draw, Kramnik solidly beat Deep Fritz twice in a row and then drew again. "We thought that we would lose very badly," says Friedel. But the pressure of an opponent that never tired wore the champion down. "We could see it in his face,” Friedel recalls. “It was rather ghastly."
Under time pressure, Kramnik slipped up and lost the next round. In game six, however, Kramnik made a dramatic move. After pondering for 42 minutes, Kramnik sacrificed a knight for tactical advantage and played directly against the computer's strength. Although the vicious attack would have overwhelmed almost any human opponent, "Fritz found a tiny little hole" and defeated Kramnik. Exhausted, he accepted two quick draws for the last two games, leaving the match tied at two victories apiece and putting Kramnik in awe of the computer's abilities.
"It plays like a very strong human. These are 'human moves,'" Kramnik said at a press conference after the match. And like a human, it seems that Deep Fritz wants another shot at an undisputed victory--both sides look forward to a rematch.