How to score this game? (Japanese rule discussion)


No, it isn’t. If white decides to resume the game it’s black’s turn, black moves to capture the center group and white can’t stop it because in order to live, white would have to throw-in-atari one of black’s left groups, which doesn’t work because black captures and white isn’t allowed to recapture. White can play atari on the other side but it’s the same. Black captures, white can’t recapture. None of black’s stones, because it’s not a regular ko. White can only recapture after black’s response to white passing. If white passes however, black leisurely takes either of white’s two groups on the left and with that, the entire board.


This is the sequence (slight adaptation from my earlier post)
White resumes the game
Black pass (or takes a white liberty)
White A3 (throw-in)
Black A2 takes ko
White A7 (second throw-in, also serves as ko threat)
Black A8 takes ko
White retakes first ko
Black whatever
White captures a black group


“White retakes ko” - Ok. Black wins by w rule violation.


You’ll need to clarify that one.


You’re not allowed to recapture.


You’re kidding, right :slight_smile:

btw by clarifying, I meant… clarifying.


I think you are conflating the confirmation phase rules with the procedure for resuming the game.

In the confirmation phase, a player can’t recapture a ko without passing.
However, a player can request to resume the game, which backs out of the scoring phase altogether and continues play with the normal ko rules, where ko threats are valid.


I’m sure it can be!

I don’t mean to say that chemistry knowledge is completely useless to a pastry chef. After all, learning the intricacies of the rules is probably not completely useless for playing go well. I just meant that one could have a PhD in chemistry, yet that alone is not sufficient for mastering the art of pastry making.


Ok, to clarify @smurph 's point:

The only way white can recapture is if they say “I’ll pass to liberate this ko”. In other words, white has to waste a whole move (and I mean, truly waste). This is what it means when the rules say: “passing is the only admissible ko threat”.

So, indeed, if white was foolish enough to allow this game to enter the scoring phase without biting the bullet and starting the ko during the game, they are basically forfeiting the whole board.

Edit: Notice that this wouldn’t actually happen on OGS. OGS does not implement Japanese rules to the fullest (I don’t think any server does). Here, you’d just resume playing, in which case either black or white could probably force the ko anyway.


That is incorrect if the game resumes. Please see the above conversation for full details.


Let’s get real here, if you both pass to scoring in a tournament with this on the board is the director really going to suggest you play out a hypothetical ko sequence according to separate rules? No, he’s going to say if you don’t start a ko the left side will all be called seki and you’ll each get four points. Most people can’t be bothered with legalistics.


@bugcat let’s get real, this is not a tournament position. This thread is a question on the interpretation of Japanese rules.

In case it was not clear, it is the same ruleset (official Japanese rules).


I mean the difference between “in-game” and “post-game” rules. I’m not going to get into a debate because I know really little about how the post-game rules work.


Yes. If the director is serious about strictly following the official Japanese rules, then applying these special ko rules is exactly what is done in the confirmation phase to resolve the life and death status of stones.

Note that in the confirmation stage, it is just a consideration of the hypothetical play out in order to determine the life and death of groups. The position is then returned to the end-game state (directly after the two passes), but with the dead stones removed, for counting.

If the tournament director did this, then they would not be following the Japanese rules. It would not be considered a seki under the official Japanese rules.

I think many people (myself included) do not like the complexity (and perhaps arbitrariness) of the Japanese rules, once they become aware of it.

That’s just the nature of the Japanese rules. Figuring out what stones can be captured during the confirmation phase uses different ko rules than normal play.


@Leira, I think most of us are in agreement that all of white’s stones would be dead if white simply let the position stand for scoring to proceed.

However, the point that @SanDiego is making, which @smurph seems to have failed to grasp, is that the game in the scoring phase can be resumed at the request of either player. This is a feature of the official Japanese rules (note that article 9.3 is referenced in the above discussion). When resuming the game, play continues as normal under the typical ko rules, which would allow white to capture 6 black stones in order to secure the life of all but 8 of their stones.


We all know what happens when you follow the rules to the letter.

You’ll get overruled.


True. That is something I don’t disagree with. The game can be resumed (presumably) at the behest of W. However, W will have to proceed and start the ko (or force black to start the ko).

My point is, under Japanese rules, there is no such thing as a seki on this position: either W proceeds to sacrifice some stones in order to save the rest, or W allows the position to enter the scoring phase and lose by the whole board (minus komi). B has no incentive to play unless W forces them to.


In the above discussion, people keep saying “according to the Japanese rules” as if the document we’re referring to is the absolute strict reference to what “Japanese rules” actually are, and something to be followed to the letter at all times.

As I understand it, it isn’t.

The documentation of the Japanese rules is a retrofit. Up until relatively recent times (as understand it) the rules were not written down at all. They were simply understood and learned by the relatively small group of people playing top level Go in Japan.

Then at some point as the game expanded it became necessary to write them down and that’s where the problem started. Because it turned out hard to write down rules that matched historical rulings. Which is not surprising - historical rulings were made based on the spirit of the game and a practical shared understanding of the rules, not a formal ruleset.

That history seems important.

They need to follow the tradition of them and spirit of them, rather than strictly following the words.

Every commentary on the rules warns that if you try to slavishly follow the words, you will get nonsense.

At the top of the rules it specifically says:

“These rules must be applied in a spirit of good sense and mutual trust between the players.”

I do agree that from time to time this can produce a dispute, and it may be unsettling to know that this might happen. Ultimately, that’s why we have referees.

Interestingly, the dispute Smurf referred to was about Ing rules, which goes to show that Japanese isn’t the only one with problems.

Amusingly, the Ing ruleset has this written on the title page:

“Absolutely No Adjudication Almost No Drawn Games”



This is an exercise, not a real tournament game (@yebeltz was quickly unmasked). Just like you would ask about a tsumego or a fuseki problem.

The interest is the exploration of the paths, more than a final decision.

From the OP:


It’s a fascinating exercise. And it’s helped me to learn a lot about the rules.

But it is easy to lose sight of the fact that it is just an exercise when people say “Yes. If the director is serious about strictly following the official Japanese rules…” and “I think many people (myself included) do not like the complexity (and perhaps arbitrariness) of the Japanese rules, once they become aware of it.”

That’s not just an exercise, that is trying to understand how this works in real life.