A new milestone in computer chess was achieved in late September when Hitech, the chess-playing computer from Carnegie-Mellon University in Pittsburgh, decisively triumphed, 3-, in its four-game match against grandmaster Arnold Denker. Denker, a former United States champion (1944-46) who was famous for his swashbuckling style and sacrificial attacks, is only semi-active nowadays and was unable to cope with the remorseless and diabolical accuracy of the chess program of the mainframe computer of the Carnegie-Mellon team, headed by Dr. Hans Berliner, a computer scientist and himself a former world champion correspondence chess player.
After drawing the first game, Hitech went on to win the final three contests.
According to Berliner, the computer scans 165,000 positions a second, which often enables it to analyze and assess certain variations that mere mortals discard out of hand as violating certain general rules that humans tend to treat as gospel.
An excellent case in point is the wonderful queen check from the edge of the board which Hitech came up with on the ninth move of today's featured game (the fourth and final in the match).
Experts are generally loath to develop the queen, lest it will present a target and will be the subject of an attack that will often cost much time. In this game, though, there is a neat contrast between Denker's early queen moves, which lost time while he isolated the White queen's pawn, and Hitech's queen check, which was the beginning of a remarkable attacking plan, perfectly calculated by the computer Hitech and obviously underestimated by the former US Champion.
The match, which was contested at the New School in New York City, offered a purse of $7,000. The prize money went into a trust fund established by Carnegie-Mellon.
Sicilian Defense Hitech Denker 1. e4 c5 2. c3 d5 (a) 3. exd5 Qxd5 4. d4 Nf6 5. Nf3 cxd4 6. cxd4 g6 7. Nc3 Qd8 8. Bc4 (b) Bg7 9. Qa4+ (c) Nbd7 10. Bxf7+ (d) Kxf7 11. Ng5+ Ke8 (e) 12. Ne6 Qb6 13. Qc4 (f) Nf8 14. Nxg7+ Kd8 15. O-O Bd7 16. Re1 Qd6 17. Bg5 Rc8 18. Qf7 Rc6 (g) 19. Nb5 Qb4 20. d5 (h) Qxb5 21. dxc6 Qxg5 22. cxd7 Nf6xd7 23. Rac1 (i) Resigns
A.The sharpest continuation. Often seen here is 2....Nf6, but the most discreet continuation is probably 2....e6, preparing for ...d5 (i.e., 3.d4, d5, and now if White plays 4.exd5, Black has the option of recapturing with the pawn, while if 4.e5, we have an Advanced Variation of the French Defense).
B.White zeroes in on f7 before Black castles.
C.Black now has no less than five interpositions, none of which is satisfactory. For example, I:9....Nc6; 10.d5; II:9.... Qd7 is refuted by either 10.Bxf7+, Kxf7; 11.Ne5+, winning the queen, or 10.Bb5, Nc6; 11.Ne5. III:9....Bd7; 10.Qb3, O-O; 11.Ne5. Now if Black defends f7, White plays 12....Qxb7; and IV:9....Nfd7; 10.Bxf7+ is even stronger than V, the text continuation. Black had to try 9....Kf8, when his prospects remain very bleak, as he is several tempi behind in an open position and has forfeited the castling privilege.
D.A stock combination frequently seen in positions of this ilk, but this one has a novel twist.
E.Black loses his queen after 11....Kf8; 12.Ne6+ and his king succumbs after 11....Kg8; 12.Qb3+ or 12.Qc4+, followed by mate on f7.
F.This move is a stinger, which Denker appears to have overlooked in his calculations. He probably anticipated only the 13.Nxg7+, Kf7; 14.Bh6, Ng4 line, which is probably good for Black, since White's advance pieces are somewhat shaky.
G.This seems necessary to guard against White's threat of 19.Rxe7, Qxe7; 20.Bxf6.
H.White prepares to pry open Black's king defenses. If the Black rook moves to a6 or b6, 21.d6 bisects and dissects Black's position.
I.The Hitech computer always selects the shortest and most accurate finish possible. Now Black cannot stop 24.Qe8 mate without bringing on catastrophic loss of material.