The Chinese Rules of Go

From James Davies,
The Rules of Go, in The Go Player's Almanac,
ed. Richard Bozulich, Ishi Press (San Jose, 1992)
Extracted, adapted, and edited by Fred Hansen

Under the traditional Chinese rules, a player's score was the maximum number of stones he could in theory play on the board. Since every groups needs two liberties to live, this rule created a two-point group tax: the player with the more separate groups lost two points for evey excess group. (In practice, one point per excess group was subtracted from the player's score and added to his opponent's score so that the total remained 361. {This does not compute; it could convert a clear winner into a loser. Only by adding two points per group could the total be made 361. --wjh}) Modern Chinese rules avoid this by counting both stones and surrounded points.

The following is the 1988 version of the official rules of the Chinese Weiqi Association. The English translation published in 1989 by Shu Rong Chess & Bridge Press (9 Qinglong-Xiang, Chengdu, Sichuan, China) has been edited here for clarity. The term `liberty' is used instead of the Chinese `breath' and the term `ko' is used instead of the Chinese terms `jie' and `tiger's mouth.' Chapters 4 and 5 and an appendix, which deals with the organization of tournaments are omitted.
James Davies

Rules of Weiqi

Chapter 1
General Rules

Section 1. Weiqi Equipment

1. The board
The board is marked with 19 parallel vertical lines and 19 parallel horizontal lines, mking 361 intersections (referred to below as `points'). Nine points on the board are dotted and called `star points'. The point in the center is also known as the `central star'. See Diagram 1.

Diagram 1.

2. The stones
Lens-shaped black and white stones are used. The number of stones is preferrably 180 of each color.

Section 2. The Move

1. One of the players, called Black, takes the black stones, the other player, called White, takes the white stones. Black makes the first move, then White, and so on in alternation until the end of the game. Only one stone can be played per move.
2. Stones are played on points on the board.
3. After a stone is played, it cannot be moved to any other point.
4. Playing alternately is the right of both players, but either player may pass.

Section 3. Liberties

A stone on the board has two to four vertically and horizontally adjacent intersections. Those which are unoccupied are called liberties.
When a stone is placed vertically or horizontally adjacent to another stone of the same color, the stones are connected and form a single unit, and their liberties are counted together.
When a stone is placed vertically or horizontally adjacent to another stone of the opposite color, it takes a liberty away from the other stone. When all the liberties of a stone or group of stones have been taken by the opposite side and no liberties are left, the stone(s) cannot remain on the board.

Section 4. Removal of stones

A stone or a group of stones without liberties is removed from the board. There are two cases:

1. When a stone is played so as to take the last remaining liberty of an opposing stone or group of stones, the opposing stone(s) are immediately removed.
2. When a stone is played so as to leave stones or groups of stones of both sides with no liberties, the opponent's stone(s) are removed.

Section 5. Forbidden points

A forbidden point is a point on the board which, if occupied by a player's stone, would leave that stone without liberties, while failing to remove any opposing stones. A player cannot play on a forbidden point. In Diagram 2, the points marked with triangles are all forbidden to plays by Black.

Diagram 2. Forbidden points

Section 6. Reappearance of the same board position

Reappearance of the same board position is forbidden throughout the game.

Section 7. The end of the game

1. The game ends when both sides agree that there will be no more moves.
2. A player may also resign during the game, in which case the game also ends.

Section 8. Living and dead stones

At the end of the game, stones which both players agree could inevitably be captured are dead. Stones that cannot be captured are alive.

Section 9. Determining the winner

At the end of the game, the winner is determined by counting stones and points.
First all the dead stones of both sides are removed from the board. Then one side's living stones are counted, including the vacant points enclosed by those stones. Vacant points situated between both sides' living stones are shared equally. A vacant point counts as one stone.
The winner is determined by comparison with 180-1/2, which is half the number of points on the board. If the total of one side's living stones and enclosed vacant points is larger than 180-1/2, then that side is the winner. If the total is less than 180-1/2, then that side loses. If the total is equal to 180-1/2, the game is a draw.
In games with compensation, the comparison is made with different numbers, according to separate rules.

Bits and Pieces of Other Sections

Chapter 2. Section 11. Compensation stones

In order to counteract Black' advantage of the first move, in national competition at present, 2-3/4 points are deducted from Black's score and added to White's in determining the result at the end of the game. {This is 5-1/2 points "komi." --wjh}

Chapter 3. Section 17. Placing of stones

2. If a player removes a stone which he has just placed on the board and places it on another point, he must replace it on the first point. The player also receives a warning from the referee.
If a player accidentally drops the stone he was about to play, he may pick it up and place it on any point.

Chapter 3. Section 19. Forbidden points

If a stone is played on a forbidden point, the move is declared invalid and the player loses his turn.

Chapter 3. Section 20. Reappearance of the same board position

1. In a ko fight, if a player recaptures on the next move, the move is declared invalid and the player loses his turn.
2. At the end of the game, in accordance with the principle which forbids reappearance of the same board position, the `moonshine-life' position is considered dead (e.g., the black stones in the lower left in Diagram 3 are dead).

Diagram 3. Moonshine life

3. In rare situations such as triple ko, quadruple ko, eternal life, and round-robin ko, if neither side will yield, the referee may declare a draw or a replay. See Diagrams 4 to 7. {This is a clear conflict with Section 6, forbidding the reappearance of the same board position. --wjh}

Diagram 4. Triple ko

Diagram 5. Four kos among three groups

Diagram 6. Eternal life

Diagram 7. Double-ko seki with double ko stones

4. According to the principle which forbids reappearance of the same board position, a player cannot refuse to end the game by reason of the position in Diagram 8 or any other similar positions.

Chapter 3. Section 21. The end of the game

1. The player whose turn it is to move may affirm {i.e., assert} the end of a game and pass. If the other player does not wish to end the game, he may continue playing, in which case the player who passed automatically regains the right to play. Play continues until both sides agree that the game has ended.
2. After both sides have agreed to end the game, if any unsettled positions remain on the board, both sides' stones in these positions are treated as alive.
3. Life and death of stones should be confirmed by both sides. Any disagreements must be settled by further actual play. {This appears to contradict the previous sentence. -- wjh}