Читать книгу The Strategy of Chess - Edward Lasker - Страница 6
ОглавлениеI. RULES OF THE GAME
A game of chess is played by two opponents on a square board consisting of sixty-four White and Black squares arranged alternately. The forces on each side comprise sixteen units, namely a King, a Queen, two Rooks, two Bishops, two Knights, and eight Pawns. All units move according to different laws, and the difference in their mobility is the criterion of their relative value and of the fighting power they contribute towards achieving the ultimate aim, namely, the capture of the opposing King. Before I can explain what is meant by the capture of the King, I must set out the rules of the game in full.
Diagram I shows the position the forces take up for the contest. The board is so placed that there is a white square at the top left-hand corner. The Rooks take up their positions at the corner squares, and next to them the Knights. Next to those again are the Bishops, and in the centre the King and Queen, the White Queen on a White square, and the Black Queen on a Black square. The eight pawns occupy the ranks immediately in front of the pieces. From this initial position, White begins the game in which the players must move alternately.
The pieces move in the following way : The Rook can move from any square it happens to be on, to any other square which it can reach in a straight line, either perpendicularly or horizontally, unless there is another piece of the same colour in the way, in which case it can only move as far as the square immediately in front of that piece. If it is an opposing piece which blocks the way, he can move on to the square that piece occupies, thereby capturing it. The piece thus captured is removed from the board. The Bishop can operate along either of the diagonals of which the square on which he is standing forms part. A Bishop on a White square can therefore never get on to a Black one.
Diag. 1.
The Queen commands both the straight and the oblique lines which start from the square she stands on, and therefore unites the power of both Rook and Bishop in her movements.
The King has similar powers to the Queen, but curtailed, inasmuch as he can only move one step at a time. He therefore only controls one neighbouring square in any direction.
The Knight plays and captures alternately on White and Black squares, and only reaches such squares as are nearest to him without being immediately adjacent ; his move is as it were composed of two steps, one square in a straight line, and one in an oblique direction. Diagram 2 will illustrate this.1
The pawns only move straight forward, one square at a time, except at their first move, when they have the option of moving two squares. In contrast to the pieces, the pawns do not capture in the way they move. They move straight forward, but they capture diagonally to the right and left, again only one square, and only forward. Therefore a pawn can only capture such pieces or pawns as occupy squares of the same colour as the square on which it stands. If, in moving two squares, a pawn traverses a square on which it could have been captured by a hostile pawn, that pawn has the right to capture it, as if it had moved only one square. This is called capturing en passant. However, this capture can only be effected on the very next move, otherwise the privilege of capturing en passant is lost.
Diag. 2.
If a player succeeds in reaching the eighth rank with one of his pawns he is entitled to call for any piece of higher grade, with the exception of the King, in place of such pawn.
Each move in a game of chess consists of the displacement of one piece only, with the exception of what is termed “castling,” in which the King and either Rook can be moved simultaneously by either player once in a game. In castling, the King moves sideways to the next square but one, and the Rook to which the King is moved is placed on the square which the King has skipped over. Castling is only allowed if neither the King nor the Rook concerned have moved before, and if there is no piece between the Rook and King.
Diagram 3 shows a position in which White has castled on the Queen’s side, and Black on the King’s side. Castling is not permitted if the King in castling must pass over a square attacked by a hostile piece. A square (or a piece) is said to be “attacked” when the square (or the piece) is in the line of action of a hostile unit. A square (or a piece) is said to be covered or protected if an opposing piece occupying that square (or capturing the piece) could itself be captured.
When attacking the King it is customary to call “check,” to notify the opponent of the fact ; for the attack on the King must be met in some way or other. This can be done by capturing the attacker or by interposing a piece (this is not possible in case of attack by a Knight or a pawn), or lastly by moving the King to a square which is not attacked. The latter must not be done by castling. If it is impossible by any of the three methods above mentioned to avoid the attack upon the King, the King is said to be checkmated, and the game is ended.
Diag. 3.
If a King is unable to move, though not attacked, and none of his remaining pieces can move, the King is said to be stalemated, and the game is drawn. A game is also drawn when neither side has sufficient material left to enforce a mate. (Compare page 63.)
If a player resigns his game before he is actually mated, he acknowledges that in the end mate is unavoidable, and the game is counted as a loss to him.
A game is null and void if it is shown that a mistake was made in setting the board or men. The same applies when in the course of the game the position and number of pieces have been altered in a manner not in accordance with the proper course of play, and the latter cannot be reconstructed from the point where the error was made.
If a player having the move touches one of his pieces he is under compulsion to move it ; if he touches a hostile piece he must capture it, provided that the piece can be properly moved or captured in either case. This rule is of no effect if the piece so touched cannot be moved or captured, as the case may be. So long as the hand has not left the piece to be moved, the latter can be placed on any accessible square. If a player touches a piece with the sole object of adjusting its position, he must apprise his opponent of his intention by saying “J’adoube” beforehand. It is best to move the King first when castling. If the Rook is moved first, and unless the King is played almost simultaneously, a doubt might arise whether castling or a Rook’s move only was intended.
If a player has castled illegally, Rook and King must be moved back, and the King must make another move, if there is a legal one. If not, any other move can be played. A player who makes an illegal move with a piece must retract that move, and make another one if possible with the same piece. If the mistake is only noticed later on, the game should be restarted from the position in which the error occurred.
II. NOTATION
A special notation has been adopted to make the study of games and positions possible, and it is necessary for students of the game to become thoroughly conversant with it. The original and earliest notation is still in use in English, French, and Spanish speaking countries. It is derived from the original position in the game, in that the squares take the names of the pieces which occupy them. Thus the corner squares are called R 1 (Rook’s square or Rook’s first), and to distinguish them from one another Q R 1 or K R 1 (Queen’s or King’s Rook’s square). The squares immediately in front are called Q R 2 or K R 2. A distinction is made between White and Black, and White’s R 1 is Black’s R 8, Black’s R 2 is White’s R 7, White’s R B 3 is Black’s K B 6, and so on. K stands for King ; Q for Queen ; R for Bishop ; Kt for Knight ; R for Rook ; and P for Pawn. In describing a capture, only the capturing and the captured pieces are mentioned, and not the squares.
When confusion is possible, it is customary to add whether King’s side or Queen’s side pieces are concerned, e.g. K R × Q Kt. In this notation it is necessary to bear in mind which Kt is the Q Kt, which R is the K R. This becomes increasingly difficult as the game goes on and pieces change their places. Many sets of chessmen have one Rook and one Knight stamped with a special sign, to show they are King’s side pieces. This is not necessary in the case of Bishops : a white K B is always on white squares, a white Q B on black squares.
A more modern notation is the algebraic notation, which has been adopted in most countries. It has the advantage of being unmistakably clear, and also more concise. Here the perpendicular lines of squares (called files) are named with the letters a-h, from left to right, always from the point of view of White, and the horizontal lines of squares (called ranks) with numbers 1-8 as before, only with the distinction that the rank on which the White pieces stand is always called the first ; thus the square we named White’s Q B 2 or Black’s Q B 7 is now called B 2 in both cases. Black’s Q B 2 (White’s Q B 7) is always B 7. In capturing, the square on which the capture takes place and not the piece captured is noted, for the sake of uniformity. In the case of pawn moves, the squares only are noted.
O—O stands for castles on the King’s side ; O—O—O stands for castles on the Queen’s side ; : or × stands for captures ; + for check.
In the following opening moves, both notations are used for the purpose of comparison :
In most books in which the algebraic notation is used, both squares of a move are written out for the benefit of the student. The moves above would then look like this :
| 1. d 2—d 4 | d 7—d 5 |
| 2. c 2—c 4 | e 7—e 6 |
| 3. Kt b 1—c 3 | c 7—c 5 |
| 4. c 4 × d 5 | e 6 × d 5 |
| 5. e 2—å 4 | d 5 × e 4 |
| 6. d 4—d 5 | Ktg 8—f 6 |
| 7. Be 1—g 5 | Bf 8—e 7 |
| 8. Ktg 1—e 2 | O—O |
To conclude : I will give the denomination of the pieces in various languages:
1. I should like to quote my friend Mr. John Hart’s clever definition of the Knight’s move, though it may not be new. If one conceives a Knight as standing on a corner square of a rectangle three squares by two, he is able to move into the corner diagonally opposite.
