Bishop (chess)

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Bishop in the standard Staunton pattern.

A bishop (♗,♝) is a piece in the board game of chess. Each player begins the game with two bishops. One starts between the king's knight and the king, the other between the queen's knight and the queen. In algebraic notation the starting squares are c1 and f1 for White's bishops, and c8 and f8 for Black's bishops.

The canonical chessmen are now dated back to Howard Staunton and the Staunton chess set. The piece's deep groove symbolizes a bishop's (or abbot's) mitre. The groove originates from the original Indian form of the piece, an elephant (the groove represented the elephant's tusks). This groove was interpreted differently in different countries as the game moved to Europe; in France, for example, the groove was taken to be a jester's cap, hence in France the bishop is called "fou" (the fool).

The bishop's move

abcdefgh
8
c8 black bishop
f8 black bishop
c1 white bishop
f1 white bishop
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abcdefgh
Initial placement of the bishops.
abcdefgh
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The black bishop can move to any of the squares marked by a black dot. The white bishop can move to any square marked by a white dot or capture the black pawn
Chess pieces

King

Queen

Rook

Bishop

Knight

Pawn

The bishop has no restrictions in distance for each move, but is limited to diagonal movement. Bishops cannot jump over other pieces. A bishop captures by occupying the square on which an enemy piece sits.

The bishops may be differentiated according to which wing they begin on, i.e. the king's bishop and queen's bishop. As a consequence of its diagonal movement, each bishop always remains on either the white or black squares, and so it is also common to refer to them as light-squared or dark-squared bishops.

Comparison to other pieces

versus rook

A rook is generally worth about two pawns more than a bishop. The bishop has access to only half of squares of the board, whereas all squares of the board are accessible to the rook. A rook on an empty board always attacks fourteen squares, whereas a bishop attacks no more than thirteen and as few as seven, depending on how near it is to the center. A king and rook can force checkmate against a lone king, while a king and bishop cannot.

versus knight

In general bishops are approximately equal in strength to knights, but depending on the game situation either may have a distinct advantage.

abcdefgh
8
a8 black rook
d8 black queen
e8 black king
h8 black rook
c7 black pawn
e7 black bishop
f7 black pawn
h7 black pawn
a6 black pawn
c6 black knight
d6 black pawn
f6 black knight
g6 black pawn
h6 white bishop
b5 black pawn
d4 black pawn
e4 white pawn
b3 white bishop
c3 white pawn
g3 white queen
h3 white pawn
a2 white pawn
b2 white pawn
f2 white pawn
g2 white pawn
a1 white rook
b1 white knight
f1 white rook
g1 white king
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77
66
55
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abcdefgh
A rare example of a bishop fork occurs after 12...Nxe4?, when the forking 13.Bd5! wins material after, e.g., Nxg3 14.Bxc6+ Qd7 15.Bxd7+ Kxd7 16.fxg3.

Bishops generally gain in relative strength towards the endgame as more pieces are captured and more open lines are available for them to operate. When the board is empty, a bishop can influence both wings simultaneously, whereas a knight would need a few moves to do so. In an open endgame, a pair of bishops is decidedly superior to either a bishop and a knight, or to two knights. A player possessing a pair of bishops has a strategic weapon in the form of a long-term threat to trade down to an advantageous endgame.

In certain positions a bishop can by itself lose a move (see triangulation and tempo), while a knight can never do so. The bishop is capable of skewering or pinning a piece, while the knight can do neither.

On the other hand, in the opening and middlegame a bishop may be hemmed in by pawns of both players, and thus be inferior to a knight which can hop over them. Furthermore, on a crowded board a knight has many opportunities to fork two enemy pieces. While it is technically possible for a bishop to fork, practical opportunities are rare. One such example occurs in the position at right, which arises from the Ruy Lopez: 1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.0-0 b5 6.Bb3 Be7?! 7.d4 d6 8.c3 Bg4 9.h3!? Bxf3 10.Qxf3 exd4 11.Qg3 g6 12.Bh6!

Game use

Good bishop and bad bishop

Lua error in package.lua at line 80: module 'Module:Chessboard/"padding: 0.5em 0; text-align: left;"' not found. A player with only one bishop should generally place their pawns on squares of the color that the bishop cannot move to. This allows the player to control squares of both colours, allows the bishop to move freely among the pawns, and helps fix enemy pawns on squares on which they can be attacked by the bishop. Such a bishop is often referred to as a "good" bishop.

Conversely, a bishop which is impeded by friendly pawns is often referred to as a "bad bishop" (or sometimes, disparagingly, a "tall pawn"). However, a "bad" bishop need not always be a weakness, especially if it is outside its own pawns' pawn chains.

In the position from the game Krasenkow versus Zvjaginsev,[1] a thicket of black pawns hems in Black's bishop on c8, so Black is effectively playing with one piece fewer than White. Although the black pawns also obstruct the white bishop on e2, it has many more attacking possibilities, and thus is a good bishop vis-a-vis Black's bad bishop. Black resigned after another ten moves.

Fianchetto

A bishop may be fianchettoed, for example after moving the g2 pawn to g3 and the bishop on f1 to g2. This can form a strong defense for the castled king on g1 and the bishop can often exert strong pressure on the long diagonal (here h1-a8). A fianchettoed bishop should generally not be given up lightly, since the resulting holes in the pawn formation may prove to be serious weaknesses, particularly if the king has castled on that side of the board.

There are nonetheless some modern opening lines where a fianchettoed bishop is given up for a knight in order to double the opponent's pawns, for example 1.d4 g6 2.c4 Bg7 3.Nc3 c5 4.d5 Bxc3+!? 5.bxc3 f5, a sharp line originated by Roman Dzindzichashvili. Giving up a fianchettoed queen bishop for a knight is usually less problematic. For example, in Karpov-Browne, San Antonio 1972, after 1.c4 c5 2.b3 Nf6 3.Bb2 g6?!, Karpov gave up his fianchettoed bishop with 4.Bxf6! gxf6 5.Nc3, doubling Black's pawns and giving him a hole on d5.[2]

Endgame

An endgame in which each player has only one bishop, one controlling the dark squares and the other the light, will often result in a draw even if one player has a pawn or two more than the other. The players tend to gain control of squares of opposite colors, and a deadlock results. In endgames with same-colored bishops, however, even a minute advantage may be enough to win.

Bishops on opposite colors

H. Wolf vs. P. Leonhardt, 1905.
abcdefgh
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d6 black bishop
f4 black pawn
g4 black pawn
h4 black king
e2 white bishop
g2 white king
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Draw with either side to move

Endgames in which player has only one bishop (and no other pieces) and the bishops are on opposite colors are often drawn, even when one side has an extra pawn or two. Many of these positions would be a win if the bishops were on the same color.

The position from Wolf versus Leonhardt (see diagram), shows an important defensive setup. Black can make no progress, since the white bishop ties the black king to defending the pawn on g4 and it also prevents the advance  ... f3+ because it would simply take the pawn. The bishop alternates between the squares d1 and e2 (Müller & Lamprecht 2001:118).

If two pawns are connected, they normally win if they reach their sixth rank, otherwise the game may be a draw (as above). If two pawns are separated by one file they usually draw, but win if they are farther apart (Fine & Benko 2003:184–204).

Efim Bogoljubov vs. Max Bluemich, 1925.
abcdefgh
8
c8 black bishop
f8 black king
f7 black pawn
g7 black pawn
a6 black pawn
c6 black pawn
g6 black pawn
c4 white pawn
e4 black pawn
b3 white pawn
e3 white bishop
h3 white pawn
a2 white pawn
f2 white pawn
g2 white pawn
d1 white king
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Position after 28 ... Kf8

In some cases with more pawns on the board, it is actually advantageous to have the bishops on opposite colors if one side has weak pawns. In the game of Efim Bogoljubov versus Max Bluemich, 1925 (see diagram), White wins because of the bishops being on opposite colors making Black weak on the black squares, the weakness of Black's isolated pawns on the queenside, and the weak doubled pawns on the kingside (Reinfeld 1947:80–81). The game continued[3]

29. Kd2 Ke7
30. Kc3 f6
31. Kd4 Be6
32. Kc5 Kd7
33. Kb6 g5
34. Kxa6 Kc7
35. Bb6+ Kc8
36. Bc5 Kc7
37. Bf8 f5
38. Bxg7 f4
39. Bf6 f3
40. gxf3 exf3
41. Bxg5 Bxh3
42. Bf4+ 1-0

See also

Notes

References

  • Alburt, Lev (December 1996), "Rules? What Rules? Part I", Chess Life: pp. 18-19 {{citation}}: |pages= has extra text (help)
  • Averbakh, Yuri (1977), Bishop Endings, Batsford, ISBN 0-7134-0096-X
  • Barden, Leonard (1980), Play better CHESS with Leonard Barden, Octopus Books Limited, p. 10, ISBN 0-7064-0967-1
  • Botvinnik, Mikhail (1972), Mikhail Botvinnik-Master of Strategy, Batsford, p. 73-75, ISBN 0-7134-6973-0
  • Brace, Edward R. (1977), An Illustrated Dictionary of Chess, Hamlyn Publishing Group, pp. 34–35, ISBN 1-55521-394-4
  • Fine, Reuben; Benko, Pal (2003), Basic Chess Endings (1941), McKay, ISBN 0-8129-3493-8
  • Müller, Karsten; Lamprecht, Frank (2001), Fundamental Chess Endings, Gambit Publications, ISBN 1-901983-53-6
  • Reinfeld, Fred (1947), Reinfeld on the End-game in Chess, Dover Publications