Dixit Magister (part 3)

This is the third part of a three-part series. To make things more convenient, here are links to the first part and the second part.

As one commenter observed after Part 1, the story is about the man-versus-machine battle. True, that’s a big part of the story, but there’s more to it. For one thing, it’s about a real game that happened between flesh-and-blood humans. I think that the story would have been vastly less interesting if that game had never happened.

But hush! I must not give away too much. On we go to the conclusion…

DIXIT MAGISTER (continued)

© Dana Mackenzie

IV.

Back in Reno, David Pruess is stewing. Emory Tate, many times Armed Forces chess champion, will say later, “David Pruess is as unflappable a player as you’ll ever see at the chessboard. He’s like Tom Cruise in Top Gun. But when Mackenzie played that queen sacrifice, I swear I saw a tremor pass over him—just the slightest ripple of concern.” Ripple or no ripple, Pruess’s big problem is that he is using vast quantities of time. He has taken an hour to play the first 11 moves, while I have used just two minutes. This will give him less time to play the remaining moves of the game.

Gradually, the game takes on a life of its own. Friedel comes over and watches Pruess squirm. Pruess departs eventually from the move order preferred by Fritz, but the overall character of the position does not change. For once in my life, I know exactly what my pieces are saying. Keep the vertical files closed, so that Black’s rooks have nothing to do. Organize the White army so that my two extra small pieces—a bishop and knight—do more work than Black’s extra queen. Sweep aside Black’s center pawns, the last obstacle to the White army. And then let the White pieces creep forward like an incoming tide. The details are different, but the strategy has all been worked out in my hundred practice games against Fritz.

Above it all, the departed queen weaves her magic spell. No one has ever seen such an early queen sacrifice, or one where it took so long for the attack to come to fruition. Every spectator, from the thoroughly distracted Tate (paying more attention to my game than his own) to the Russian grandmaster Victor Mikhalevski, is wondering the same thing. Could this sacrifice possibly be sound? Why is White’s position getting sweeter and sweeter, while Black’s shrivels up like a prune?

On move 36, thirty moves after the sacrifice, Black’s extra queen finally falls, like a giant being swarmed over by ants. The rest is easy. Finally, ten moves later, Pruess stops the clock and extends his hand, the universal gesture of resignation.

V.

An hour after my game with David Pruess ends, I wander into the skittles room, a side room where the players go to blow off steam after four hours of intense concentration. There is bedlam in the room. Nothing unusual about that. Then I realize it is my game that they are arguing about. A circle of ten or twelve players is analyzing a position from around move 17. Mikhalevski is saying that I should have grabbed a pawn. Pruess is sitting at the table, too, looking somewhat bemused, daring anyone to show him where he made a mistake. Then one of the gathered players, international master Jesse Kraai, spots me and says to the assembled crowd, “Why don’t you ask the man himself? Here he is!”

I tell them about my two-year quest. Giving up my queen on move six started as a crazy idea, but like lots of crazy ideas, it seemed right enough that I couldn’t give up on it. I played it against Fritz over and over. I have to be honest: Most of the time I lost, but never did I feel that the computer was getting anywhere close to the truth. It was winning only because of mistakes I made later in the game.

Gradually, as I understood what the pieces were saying, the queen sacrifice turned into a complete concept, not just an opening variation. The concept was that you could win with two smaller pieces against a queen. You just had to be patient enough, keep the position closed, and let the initiative gather momentum over a period of ten or twenty moves—too long for a computer to calculate. In this way, I could beat a computer program that was supposed to be better than any human alive, and the computer would never understand why.

Kraai’s voice rises above the hubbub as he proclaims to all who are listening that this was the greatest game of all time. (It’s not, but I appreciate the compliment.) Tate, the former Air Force sergeant, has been helping himself to the casino’s free cocktails. He is in fine form, witty and self-assured, every utterance an oration. Mikhalevski, sitting next to me, is all dour skepticism. Kraai chortles as I correct Mikhalevski, explaining the strategy I had developed over two years of study: the pawn talking back to the grandmaster. “Listen to the man!” Kraai scolds Mikhalevski. “Let the master speak!”

As for Pruess, he accepts the defeat with impeccable sportsmanship and good humor. I tell him that his only mistake was being too brave. He was the first person I had ever played who had enough courage to play the “computer move,” bishop to g4, and leave his king’s fortress unguarded.

One game against a human proves ever so much more than a hundred against a computer. And yet at the same time, it proves almost nothing. The queen sacrifice will have to be played by other players before we can be sure whether it is justified, or only a glittering illusion. My greatest hope is that the debate will go on forever. The circle of players in the skittles room will argue late into the night, and then they will come back the next day and argue some more. The computers will continue to think they are winning, and yet will continue to lose. The departed queen will still weave her web of fascination and mystery, and hold her secrets close.

§ THE END §