Differences between the Korean 1992 Rules and the Applicable Traditional Japanese Rules

Version 1; 2008-04-17; Robert Jasiek

Dead Stones in Sekis

Rule Text

Article 17. Kyega (counting the Score)

The dead stones are removed and added to prisoners.

Commentary

It is unclear whether dead stones may be removed from sekis or whether that has to be played out before the end of the alternation. Under the Applicable Traditional Japanese Rules, this is clear.

Perfect Pass

Rule Text

Article 15. Daeguk Jongryo (the end of the endgame)

Daeguk Jongryo is reached when there are no profitable moves left.

Interpretation

A player may not pass if a play exists that improves the score for him.

Commentary

The rule is superfluous. It is kept only because of tradition. The official Japanese rules have stopped usage of such rules in 1989. Explaining the rule by precise rules would require definitions of hypothetical-sequence, hypothetical-strategy, compatible, and force like in the Japanese 2003 Rules model ruleset. The Applicable Traditional Japanese Rules do not contain such a superfluous rule.

Play out during the Alternation

Rule Text

The Additional Rules (Article 1, 2)

Article 1. The Definition and principle of the Additional Rules [...]

2.The Additional Rules are intended to come down on the side with the strongest claim using common Baduk logic. When this is not clear the situation must be played out.

3.If the Additional Rules are insufficient for a game position in a toumament, the KBA will adjudicate.

Interpretation

A player may not pass if application of the perfect pass rule is unclear. At the same time, the rules should not force a player to improve the score for his opponent. These two aspects considered together may be ambiguous and then the KBA makes an unpredictable decision.

Commentary

The rules are superfluous and very unclear. In the Applicable Traditional Japanese Rules, rules of such great unclarity are not needed.

Clearly More Ko Threats

Rule Text

Article 2. Reinforcement

1)The last Kongbae (neutral point) and reinforcement In Figure 1 Black 3 is an efficient move as it will ahead to Bik (seki, a local stalemate)
In Figure 2 If Black 2 is the last Kongbae, Black should indicate an intention to continue. If White gives up Chaksu, then Black may press an attack.
 
2)In Figure 3-1 If Black clearly has more Paegam (ko threats), Black A is not needed.
In Figure 3-2 White 1 should be sufficient to capture all the Black stones. If white has clearly more Paegam no further move is need.

Interpretation

A player does not need to reinforce if he has clearly more ko threats.

Commentary

Reinforcement (here for kos) could not be defined precisely yet. It requires quite some further research by theoreticians. Until then the reference in the rules to reinforcement is ambiguous. Ko threat and number of ko threats could not be defined precisely yet. It requires much further research by theoreticians. Until then the reference in the rules to ko threats and number of ko threats is ambiguous. In this context, speaking of "clearly" more ko threats deceives the reader of the rules.

In particular, not every intermediate move is a ko threat for the purpose of the Korean 1992 Rules. Numbers of ko threats are not counted easily as something linear but depend on game trees and the mutual fight about them. The purpose for that ko threats are searched is unclear: Is it sufficient to win the particular ko? Or is it necessary to optimize the score for oneself? When there are several kos on the board, then some ko threats for one ko might not be a ko threat for another ko and moves in one ko might be ko threats for the other and vice versa. An unambiguous way of solution is to go for the aim of optimizing the score for oneself, however, this is research rather than what the rules would already be saying.

The rules are superfluous. They are kept only because of tradition. The official Japanese rules have stopped usage of similar rules, although with much more restricted validity, in 1989. Explaining the rules by precise rules would require definitions of hypothetical-sequence, hypothetical-strategy, compatible, and force like in the Japanese 2003 Rules model ruleset and many more definitions to be found in future research. The Applicable Traditional Japanese Rules do not contain such superfluous rules.

Long Cycles and Void Game

Rule Text

Article 20. Musungbu (a Void Game)

If a board position is repeated and neither side is willing to give up the position, the game is annulled.

Commentary

This is very similar to the official Japanese no result rule. Both the Korean 1992 Rules and the Japanese 1989 Rules are incomplete because strategy cannot decide whether a void game or a game with a particular score is better. The Applicable Traditional Japanese Rules are more precise here intentionally so that the players can always make meaningful strategic decisions about long cycles.

Long Cycles Playout

Rule Text

5) Triple Pae and circulation Pae and so on follow the play-out rule. If neither player gives up, the repetition will annul the game.

Interpretation

A player may not pass if he could force a cycle during that an equal number of black and white stones are captured.

Commentary

The ambiguous and incomplete rule is used because of tradition and as an emergency measure to avoid having to define life and death sufficiently general for also long cycle shapes. Explaining the rule by precise rules would require definitions of hypothetical-sequence, hypothetical-strategy, compatible, and force like in the Japanese 2003 Rules model ruleset. The Applicable Traditional Japanese Rules do not need such a solution because they use the Fixed Ko Rule during the analysis phase.

Triple Ko with One Eye

Rule Text

Article 3. Life and Death [...]

4) Triple Pae (ko) with one eye in a capturing race

In Figure 10 [triple ko with one external ko mouth], Black's group is dead because White deemed to have the only claim, but if elsewhere there is a double pae or some such equal claim, this position must be played out. [...]

Interpretation

A shape triple ko with one eye in a capturing race exceptionally invalides the long cycles playout rule and applies only unless the latter applies to both players for the whole board position. If the exception applies, the stones inside the shape and of the player without the eye are dead.

Commentary

The rule is ambiguous, illogical, and superfluous. It is kept only because of tradition. The rule is ambiguous because the shape, "capturing race", and "eye" are undefined. The rule is illogical because the exception to the long cycles playout rule and the justification ("White deemed to have the only claim") are introduced arbitrarily. The Japanese 1989 Rules produce the same status for shape by other ambiguous and exceptional means (the pass for a particular ko rules). The Applicable Traditional Japanese Rules omit such a superfluous exception but lead to a different status assessment for the rare shape.

In the shape, the player without an eye cannot force a cycle under a two pass rule while his opponent can force a cycle. If one wanted to use that as a criterion, then one would have to distinguish stable and instable states of long cycle shapes for the long cycles playout rule. This would become like modelling Ing ko rules. Therefore the current interpretation of the long cycle playout rule is simpler than trying to get a precise description of available strategies in the triple ko with one eye shape.

Appendix

Comparison between the Korean 1992 and the Japanese 1989 Rules

Both rulesets allow the players to develop strategy for most part of the alternation and rely on perfect play during the status analysis phase. The rulesets differ late during the alternation: Already then the Korean 1992 Rules rob the players part of their strategic freedom. In particular, they may not make a strategic mistake when passing. The Korean 1992 Rules are the factually more difficult ruleset because explaining them is like explaining the Japanese 1989 Rules plus the concepts perfect pass, number of ko threats, etc.

Comparison between the Korean 1992 and the Japanese 2003 Rules

Apart from the differences between the Korean 1992 Rules and the Applicable Traditional Japanese Rules, which are also differences between the former and the Japanese 2003 Rules, the Korean 1992 Rules are very close to the Japanese 2003 Rules: The basic rules and diagrams for life, death, and seki are explained very well by the concepts uncapturable, capturable-1, and capturable-2.

Unification of Korean and Japanese Rules?

The practical differences between the Korean 1992 Rules and the Japanese 1989 Rules are small and created almost only by superfluous rules for rare exceptions. It requires traditional hardliners on both sides to justify still prevented unification. More and more detailed research by rules experts has been used as a pretence but the opposite is true: Model rulesets have proven that both rulesets are based on the same core and that their remaining differences are caused by exceptions and superfluous parts in the official rulesets themselves.

Inapplicable for Amateurs

The Korean 1992 Rules are inapplicable for amateurs because they do make strategic mistakes when passing and thereby violate the rules, because amateurs do not want to read, learn, and remember the many exceptional rules, and because amateurs can have great difficulties to approach life and death judgement correctly.

General Conclusion

The Korean 1992 Rules are an attempt to write down Japanese style rules. Since those came to Korea rather late, there has been less time to study the related rules theory. However, in view of the far more developed research of amateur rules experts, national pride and (relatively short) tradition are the only noteworthy reasons to keep the rules. They could be improved very much if the Korean professionals wanted to apply some concepts of various model rulesets.