One of the many differences between human beings and computers is that computers do not have blind spots, as world chess champion Vladimir Kramnik did in game two of his match against the Deep Fritz software on Monday.
After outplaying the machine for most of the game, and with a clear draw in hand, he made a colossal blunder that allowed checkmate on the move, The Associated Press news agency reports. Deep Fritz now leads the six-game match, 1.5-0.5
«It was very strange to me. I cannot find an explanation», Kramnik told reporters after the game. «I was not tired». He looked remarkably calm and composed despite the loss.
Time pressure was not a factor. Kramnik had 33 minutes to make five moves when he went over the cliff.
The machine’s handlers chose to open with the queen pawn (the program’s opening book is set before the match) and Kramnik responded with the Queen’s Gambit Accepted, a solid line that fits his style and avoids the computer’s advantages.
After fifteen moves, American grandmaster Yasser Seirawan said that Kramnik was “in no danger.” Kramnik had the advantage on the queenside and Fritz’s chances on the kingside seemed illusory.
In the moves that followed, Kramnik obtained a two-on-one queenside pawn majority. He allowed the f-file to be opened and allowed his f-pawn to fall to a queen check. But his king seemed safe in the corner on h8.
Still, the machine seemed to have enough play to hold the position. According to its operator, Mathias Feist, Fritz rated itself down two-thirds of a pawn.
Kramnik said afterward, “My position was simply better without any risk.”
On move 31, Kramnik pushed his a-pawn, perhaps prematurely, and entered a series of forced moves that should have ended in a draw. It seems likely that Kramnik had already calculated the line they were to follow, only without noticing the checkmate threat ahead.
Kramnik could have avoided the checkmate by simply moving his king and the game would have quickly ended in a draw. Instead, he moved his queen, offering to exchange queens into an ending that his a-pawn would have quickly decided in his favor.
Unfortunately, he completely overlooked the checkmate. Seirawan pointed out that delivering checkmate was the only move that did not lose for the computer.
The blunder, which Seirawan called «a tragedy», was one that even the weakest amateurs would not ordinarily make and almost unheard of at this level.
The first game of the match was drawn on Saturday. Kramnik achieved a considerable advantage and some observers, notably former world champion Garry Kasparov, felt that Kramnik may have missed a winning continuation. Game three is scheduled for Wednesday. Kramnik will have White. |
