Pursuits: Chess

THERE ARE two ways to play against a computer: you can either ignore the fact that it is a machine and just treat it like any other opponent, or you can adopt a specifically anti-silicon strategy against it. Generally the second strategy is more successful, as the following two games from the Lippstadt tournament attest.

Both feature the new star on the computer scene, a beast called Zugzwang, which finished third in the tournament with a performance that included this victory over the winner of the event.

White: Zugzwang

Black: Luke McShane

Lippstadt1998

1 e4 c5 13 Nf3 Bxf3

2 Nf3 d6 14 Qxf3 Qxe5

3 d4 cxd4 15 Qxb7 Rd8

4 Nxd4 Nf6 16 Rhe1 Qa5

5 Nc3 a6 17 Nd5 Nxd5

6 Bg5 Nbd7 18 Bxd5 f5

7 Bc4 h6 19 b4 Qa3

8 Bxf6 Nxf6 20 Qc6+ Rd7

9 Qe2 Qa5 21 c3 e5

10 0-0-0 Qg5+ 22 Rxe5+ dxe5

11 Kb1 g6 23 Be6 Be7

12 e5 Bg4 24 Qc8+ resigns

After playing a slightly unusual opening (6...Nbd7 is rarely seen) Black's strategy led to just the sort of dynamic, open position in which computers excel. After 12.e5! he was in great trouble, since 12...Qxe5 13.Qxe5 dxe5 14.Ndb5! axb5 15.Nxb5 wins for White. The machine even polished things off with a nice combination beginning with 22.Rxe5+! At the end 24...Rd8 25.Rxd8+ Bxd8 26.Qd7+ Kf8 27.Qf7 is mate.

Now here's the right way to do it. If there's one thing a computer cannot resist, it's a free pawn. The machine had apparently not been told about the potency of the pawn sacrifice in this line of Petroff's Defence. Its decision to grab a second one with 11.Qxg7 was far too greedy, and by the time it had succumbed to the temptation of a third course with 19.Qxf7, poor old Zugzwang was completely lost.

White: Zugzwang

Black: D. Pavasovic

Lippstadt 1998

1 e4 e5 13 g3 Rg6

2 Nf3 Nf6 14 Qh5 Bg4

3 d4 Nxe4 15 Qd5 h5

4 Bd3 d5 16 Nc3 Kb8

5 Nxe5 Nd7 17 Ne4 Bf3

6 Qe2 Nxe5 18 Nc5 Qg4

7 Bxe4 dxe4 19 Qxf7 h4

8 Qxe4 Be6 20 Nd7+ Ka8

9 Qxe5 Qd7 21 Re1 Rgg8

10 0-0 Bd6 22 Qe6 hxg3

11 Qxg7 0-0-0 23 fxg3 Qh5

12 Qh6 Rdg8 White resigned