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“Tricky” chess positions

I’ve recently been reminded of an old chess lesson I learned many years ago. An acquaintance was asking me about the relative values of the pieces, information which I was happy to provide:

Pawn = 1
Knight = 3
Bishop = 3.5 (roughly)
Rook = 5
Queen = 9
King = Infinite (but about 3 as an attacker or defender in an endgame)

I was quick to point out the caveat that a Knight is actually worth more than a Bishop in a closed game, and that a “good” Bishop was worth more than a “bad” one. But I also threw out another warning which seemed to baffle my acquaintance: “Don’t put that much stock in ‘counting points’ because the specific material imbalance is far more important, plus other factors such as space advantages come into play as well.”

Did I say “baffle”? The guy was totally confused. He’d been learning chess from some antiquated beginner book which seemed to indicate that being ahead on “points” is all that matters, and that any trade is a good trade as long as you come out ahead on “points”.

I’m sorry to say that I once experienced the same deficiency in my own chess education; back in high school I had a teacher who was big on the idea of “grabbing material”. It required many years (and more than one poisoned pawn) for me to unlearn that lesson.

Properly evaluating a position requires much more from a chessplayer than the ability to “count points”. Here’s an example. Take a look at this position for a second, count to three, and then quickly say aloud who you think is ahead in the following position:

OK, now — quick! What’s your answer?

If you did this exercise according to my instructions, allowing yourself no more than three or four seconds to examine the board, I’ll bet dollars to donuts you said “Black”; after all, Black’s ahead by a Queen, Rook, and Knight for two pawns (or Queen, Rook, and one pawn if you’re playing “count the points”). I won’t say you’re necessarily wrong here, but there are a pile of problems with that answer, not the least of which is the fact that I didn’t tell you whose turn it is to move. Ooooops…

Look again. This is a great position; in fact, it’s a classic from an actual game. If it’s Black’s turn to move he mates instantly with …Qxg2#, so in this regard the “point count” doesn’t matter anyway. But I’ve tricked you a little: it’s not Black’s turn to move in this position — it’s White’s move. And in this case the point count definitely doesn’t matter because White mates with Bxe7#.

This is arguably one of the most famous positions in chess history, the next-to-last position from the “Evergreen Game”, played in 1852 between the great Adolf Anderssen and Jean Dufresne. The game has nothing to do with Christmas trees either; it’s called “evergreen” because  no matter how many times you replay it, the game still blows your mind each and every time:

Anderssen,Adolf – Dufresne,Jean [C52]
Berlin, 1852

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.b4 Bxb4 5.c3 Ba5 6.d4 exd4 7.0-0 d3 8.Qb3 Qf6 9.e5 Qg6 10.Re1 Nge7 11.Ba3 b5 12.Qxb5 Rb8 13.Qa4 Bb6 14.Nbd2 Bb7 15.Ne4 Qf5 16.Bxd3 Qh5 17.Nf6+ gxf6 18.exf6 Rg8 19.Rad1 Qxf3

At this point Dufresne threatens 20…Qxg2#, but he never gets the chance to play it. Anderssen launches a series of sacrificial checks which end in mate.

20.Rxe7+ Nxe7

To modern eyes, there is a flaw in Anderssen’s analysis. Dufresne didn’t have to capture on e7: he could instead have played 20…Kd8 21.Rxd7+ Kc8 22.Rd8+ Kxd8 23.Bf5+ (discovered check) Qxd1+ 24.Qxd1 and Black’s still in the game. But we need to bear in mind that this was the “Romantic Era”, in which it was considered unmanly to refuse to accept an offered sacrifice. Anderssen counted on this, which is why his sacrificial combination works. After 20…Nxe7, mate is forced:

21.Qxd7+ Kxd7 22.Bf5+ Ke8 23.Bd7+ Kf8 24.Bxe7# 1-0

Dufresne’s reaction to the move 20.Rxe7+ is a wonderful illustration of why “bean counting” doesn’t always work and why we shouldn’t ourselves fall prey to the blind temptation to just grab material for its own sake. Dufresne not only lost the game, but probably also spent the rest of his life hearing, “Oh! You’re the guy who lost that game!” from chessplayers he’d meet.

If you got hoodwinked by this little position, you shouldn’t feel badly about it — even chess computers sometimes get suckered by big material advantages. Here’s a famous example:

Sure, White’s a Rook up, but the position’s dead drawn — the pawns are locked and neither player can make any progress, so the extra Rook doesn’t mean doodly-squat. Unlike the first position with which I tricked you this one’s easy to figure out, and the side to move doesn’t matter — it’s drawn either way.

But almost all chess computers mess this position up. I checked this position using more than a dozen chess engines and all but one of them showed White to be ahead by more than a Rook (because of the space advantage provided by the White pawns). The only chess engine to come close to getting it right was Shredder 12 which evaluated the position as “=” (but still showed White with a 0.13 pawn advantage for some odd reason, even after a 33-ply search).

The moral of the story is that “bean counting” (that is, just counting up the captured material) can sometimes be a useful start toward arriving at a valid positional analysis, but it’s not the only available tool and is seldom the best one.

Shredder12 is available right now from ChessCentral and, if you buy it from us, you’ll get free technical support provided by yours truly should the need arise.

Have fun! — Steve


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