Saturday 13 December 2008

In the twilight zone of chess rules




White to mate i 2 - Composer unknown

I suppose you know the problem above, it is an old hat. If not it does not really matter. But some fifty years ago your ignorance could have cost quite a few beers (or - sorry! - cups of coffee) at your club (or pub).

The intended solution is: 1. a8R Kh1 2. 0-0-0+ mate!

The last move is absolutely legal, the rook in question has not moved and there are no threatened squares between the rook and the king. Or rather...it WAS legal. Not that many years ago FIDEs rules was verified with an extra item on castling saying: "The king and the rook must be on the same rank". So there goes that problem (together with some others with the same theme), into the historical museum of chess curiosities.
Sorry to say, the same goes for this nice little problem:



White to mate in 2- N. Elkies
Add a black B8: White to mate in 2

Now we are on the track, that should not be that difficult. White plays 1. f8 black B, and no matter what it is 2. Nf7+ mate next move. If you put a black bishop at f8 i the position, the solution is 1. fxg8 black R, with again 2. Nf7+ mate to come.

This sort of "over promotion" was also legal once, or rather: It was not explicitly stated, that it was not. Now the rules says that you can promote to a queen, rook, bishop, or knight of the same color - no more no less. No less? Yes, in the 19. century there were in fact some proponents (even Steinitz it is told) of the right to promote to a pawn, a "dummy pawn" as it was called. You may ask: For what purpose? To counter that question, this position was composed at the time:


White to move and draw

Yes, white plays 1. bxa8P! and if black takes the bishop at h3, it is stalemate. Otherwise white takes on g2 and gain a fortress with the opposite coloured bishops.

Indeed, some nice problem has fallen with this ongoing tightening of the rules. One I am especially fond of is this, also from the good old days:


White to mate in 3 - Emil Palkoska, 1910

And that one you should try to solve for yourself - you have been given enough hints!

Ok, you may say that this is all old stuff, very entertaining but with no relevance for nowadays chess. So? Well, look at this endgame study which circulated among the chess insiders in the 80es:


White to move and win - my version (from memory)

I believe I have read somewhere that the composer is from Dar-Es-Salaam, but I can not find sources for that.

The solution is: 1. Kf7, Nd6+ 2. g7+!, Kh7 3. g8D+ and mate next move.

Then you may object that white is in check, in fact a double check, when he unaffectedly moves his little pawn at the second move. Yes, he is in check BEFORE the move, but is he after? You see, at that time the rules stated that the king is in check "...when the square it occupies is threatened by one or TWO of the opponents pieces." So the check is elegantly parried by making the kings square threatened by THREE pieces!

Relax, nowadays the rules state that the square in question must be threatened by "..one or more of the opponents pieces".

One also quite recent puzzle arises after the well known opening moves: 1. e4, e5 2. Bc4, Nf6. Now white moves and wins! You simply play 3. Qxf7+ mate! As you might know, checkmate ends the game immediately without any question. But whites last move was illegal, you may object. Yes, right, but if an illegal move is made, you have to protest before the game has come to an end, after that it is too late! Well, now they have added to the rule, that checkmate finishes the game under the condition that the checkmating move was legal.

FIDES commission of rules was at hard work in the end-80es and 90es. At the congresses in 1992 and 1997 they came up with some revision, up tightening and complementing of the rules, that makes puzzles and compositions like the above almost impossible. That is, one the theme on what the pieces actually can do on the board.

But there are still twilight zones in the rules, not least because new rules are introduced that can lead to a games abrupt finish.



In this position white is in the move, when the mobile phone of the player of the black pieces rings. What should be the result of the game?

By closer examination of the position you will find that the game in fact already has come to an end before the tragic incident with the phone. If white moves his knight it is stalemate. If the bishop goes to a7, black has to take it. The same goes if white moves his king, in both cases ending up with insufficient material. In fact blacks last move must have been Ka7-a8 and whites move before that b7-b8B, and already after that move the game has ended. It has reached a so called "dead position", as stated in the FIDE rules:


"The game is drawn when a position has arisen in which neither player can checkmate the opponent`s king with any series of legal moves. The game is said to end in a `dead position`. "

So, in principal both players should have received a warning from the arbiter after b7-b8B for not playing according to the rules...

If you want more of this "dead reckoning", I recommend you this site:

http://www.geocities.com/anselan/chess.html



Ok, now I am maybe pushing it too far, or rather really exploring unknown territory: In this position it can be either white or black in the move. What happens then if the mobile phone of the player in the move rings?

If you study the position, you will find that who ever is in the move and what ever he moves, it is checkmate. So, I guess that if the white players phone rings he is lost, but that his opponent can only be given a half point, given that he had no possible way to win the game according to the rules.



Thomas Volet, 2006

And now, at the final, it gets really difficult. The position above was published with the stipulation: "What will be the outcome?"

By a retrograde analysis (you just try it!) it is possible to state that if white is in the move, the last 100 half moves have been without pawn moves or captures. But if black is in the move, there has only been 99. In the position both black and white can give checkmate, but without capturing ore moving a pawn.

So this is about the 50-moves rule, on which FIDE states: "The game is drawn, upon a correct claim by the player having the move, if....the last 50 consecutive moves have been made by each player without the movement of any pawn and without any capture."

And so what? If it is blacks move and he plays Rd8+ mate, can white then "claim" a draw? I really do not know. But a blogger at the chessproblem.net has some distinct opinions on that, he even claims there are some "inconsistencies" in the FIDE rules! You would not be surprised...Read and judge for yourself at:

http://www.chessproblem.net/viewtopic.php?t=128


Who moved last?

After you hopefully gained some insights from the above, you should be able to solve this little puzzle. And after doing that, you may use it for teasing your local club arbiter.

And if you have become - or are - keen on such off beat chess problems, I would like to recommend "Outrageous chess problems" by Burt Hochberg, New York 1999. But do not read it just before bedtime!

2 comments:

Anonymous said...

The solution for the last puzzle?

Anonymous said...

White...only legal move :o)