Stalemate

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Stalemate is a situation in chess where the player whose turn it is to move has no legal moves but is not in check. Stalemate ends the game, with the result a draw. However, in certain chess variants, such as suicide chess, stalemate is not necessarily a draw, and is deemed a win for either (a) the player with fewer pieces (a draw results if the players have the same number of pieces) or (b) the stalemated player.

Stalemate has also become a widely used metaphor for other situations where there is a conflict or contest between two parties, such as war or political negotiations, and neither side is able to achieve victory, resulting in what is also called a dead heat, standoff, or deadlock. In that usage, unlike in chess, "stalemate" often refers to a temporary impasse that is ultimately resolved.

1 Stalemate in chess
2 History of stalemate
3 Peculiar stalemates
4 See also
5 References
6 External links

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Stalemate in chess

Image:Four examples of stalemate.png

With Black to move, the black king is stalemated in each of the four position in the diagram at the right. Stalemate is an important factor in the endgame - the set-up in the top-right of this diagram, for example, quite frequently occurs in play, and the position in the bottom-left is an example of a pawn being worth as much as a queen. (Even if it were White's move, there is no way to avoid this stalemate without allowing Black's pawn to promote. White can, however, win the resulting queen versus queen ending if his king is close enough. For instance, if White's king is on d5 (see algebraic chess notation), he wins with 1.Qd1+ Kb2 2.Qd2+ Kb1 3.Kc4! a1(Q) 4.Kb3, when Black cannot avoid checkmate.) Stalemates of this sort can often save a player from losing an apparently hopeless position.

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Stalemate can also occur with more pieces on the board. The position at left occurred in Gelfand-Kramnik, FIDE Candidates match, game 6, Sanghi Nagar 1994. Kramnik (Black), down two pawns and on the defensive, would be very happy with a draw. Gelfand (White) has just played 67.Re7? (from e4), a strong-looking move that threatens 68.Qxf6, winning a third pawn, or 68.Rc7, further constricting Black. Black responded 67...Qc1! If White takes Black's undefended rook with 68.Qxd8, Black draws with 68...Qh1+ 69.Kg3 Qh2+!, forcing 70.Kxh2 stalemate.

If White avoids the stalemate with 68.Rxg7+ Kxg7 69.Qxd8, Black draws by perpetual check with 69...Qh1+ 70.Kg3 Qg1+ 71.Kf4 Qc1+! 72.Ke4 Qc6+! 73.Kd3!? (73.d5 Qc4+; 73.Qd5 Qc2+) Qxf3+! 74.Kd2 Qg2+! 75.Kc3 Qc6+ 76.Kb4 Qb5+ 77.Ka3 Qd3+. Gelfand played 68.d5 instead, but still only drew.

A piece that is sacrificed to bring about stalemate is sometimes termed a desperado piece. Many draws have been saved this way, two of the best known examples being Evans-Reshevsky, USA 1963 and Pilnick-Reshevsky, U.S. Championship 1942 (scroll down to #24). Keres-Fischer, Curacao 1962 is another famous game saved by the possibility of stalemate, although Fischer avoided the stalemating lines and allowed Keres to draw by perpetual check instead.

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A common misconception

A fairly common misconception among chess novices, especially children, is that if the king has no legal move and isn't in check, the game is a stalemate. Obviously this is not the case, since it would make any opening a stalemate; but sometimes young children, in the endgame, claim nonexistent stalemates when they cannot legally move the king, but have other pieces that can be moved. Actually, the player must have no legal move of any piece in order for the position to be stalemate — if the player has any pieces that can move, it is not stalemate.

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Stalemate in studies

Stalemate is a frequent theme in endgame studies and other chess compositions. An example is the "White to Play and Draw" problem at right, composed by Frederick Rhine in 2005. The main line runs 1.Ne5+! (Black wins after 1.Nb4+? Kb5! or 1.Qe8+? Bxe8 2.Ne5+ Kb5! 3.Rxb2+ Nb3) Bxe5 (After 1...Kb5? 2.Rxb2+ Nb3 3.Rxc4! Qxe3 (best; 3...Qb8+ 4.Kd7 Qxh8 5.Rxb3+ forces checkmate) 4.Rxb3+! Qxb3 5.Qh1! Bf5+ 6.Kd8! Qxc4 (best) 7.Nxc4 Kxc4 8.Qf3, White will easily draw at least. According to endgame databases, with perfect play by both sides White wins in 62 more moves.) 2.Qe8+! (2.Qxe5? Qb7+ 3.Kd8 Qd7#) Bxe8 3.Rh6+ Bd6 (3...Kb5 4.Rxb6+ Kxb6 5.Nxc4+ also leads to a drawn endgame) 4.Rxd6+! Kxd6 5.Nxc4+! Nxc4 6.Rxb6+ Nxb6+ (Moving the king is actually a better try, but the resulting endgame of two knights and a bishop against a rook is also drawn with correct play, as in Karpov-Kasparov, Tilburg 1991.) 7.Kd8! Black is three pieces ahead, but if White is allowed to take the bishop, the two knights are insufficient to force checkmate. The only way to save the bishop is to move it, resulting in stalemate.

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Stalemate in problems

Some chess problems have a stipulation for "White to move and stalemate black in n moves" (rather than the more common "White to move and checkmate black in n moves").

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Problemists have also tried to construct the shortest possible game ending in stalemate: Sam Loyd devised one just ten moves long (1.e3 a5 2.Qh5 Ra6 3.Qxa5 h5 4.Qxc7 Rah6 5.h4 f6 6.Qxd7+ Kf7 7.Qxb7 Qd3 8.Qxb8 Qh7 9.Qxc8 Kg6 10.Qe6 -- see diagram at left below). A similar stalemate is reached after 1.d4 c5 2.dc f6 3.Qxd7+ Kf7 4.Qxd8 Bf5 5.Qxb8 h5 6.Qxa8 Rh6 7.Qxb7 a6 8.Qxa6 Bh7 9.h4 Kg6 10.Qe6 (Frederick Rhine). Loyd also demonstrated that stalemate can occur with all the pieces on the board (1.d4 d6 2.Qd2 e5 3.a4 e4 4.Qf4 f5 5.h3 Be7 6.Qh2 Be6 7.Ra3 c5 8.Rg3 Qa5+ 9.Nd2 Bh4 10.f3 Bb3 11.d5 e3 12.c4 f4 -- see diagram at right below).

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History of stalemate

The stalemate rule has a somewhat convoluted history. In the forerunners to modern chess, such as shatranj, stalemate was a win for the side administering it, and this rule persisted for a while in chess, although when playing for money, a win by stalemate sometimes only won half the stake. According to H. J. R. Murray's A History of Chess (Oxford University Press, 1913), the rule for a time in England was that stalemate was a loss for the player administering it. The modern rule that stalemate is a draw became universally adopted only in the 19th century.

Assume that Black's king is stalemated. Throughout history, a stalemate has at various times been (Davidson 1949:65-66):

A win for White (10th century Arabia)
A half-win for White (18th century Spain)
A win for Black (17th century Russia and in Great Britain into the 19th century)
Not allowed. If White made a move that would stalemate Black, he had to retract it and make a different move (Eastern Asia until the early 20th century)
Black forfeits a turn to move (medieval France)
A draw (started in 14th century Italy and spread through Europe)

There have been calls to make a stalemate a win for the side causing the stalemate. The effect of such a rule would be a greater emphasis on the material on the board. An extra pawn would be a much greater advantage than it is today, e.g. king and pawn versus king would always be a win unless the defending king were able to capture the pawn.

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Peculiar stalemates

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There are peculiar chess compositions featuring double stalemate. At right is a double stalemate position, in which neither side has a legal move. Such positions are not seen in practical play. There is also a bizarre chess variant, Patt-schach, that begins from a double stalemate position.

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