Is an unfinished Ko worth a point in Japanese scoring?

I’m not sure if we should have marked F1 as a non-scoring intersection in this game:

I could have captured the Ko once more, but white had at least two more Ko threats, so I passed.

For future reference, did we score F1 correctly as a point for black, or is that supposed to be treated somehow like a seki? I had a look at Sensei’s Library but didn’t find an example like this.


Not fighting the honor ko? /me shakes head sadly

I think you should have urged Black to fill haha

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F1 should not be a point for Black. Black should have filled before passing.

Technically, under the modern rules, the Black stone at G1 is dead, but not removed (since it does not reside in territory). Yes, Japanese rules are weird like that. Sometimes dead stones are not removed.

This type of situation has come up in historic rules disputes before the codification of the 1989 Japanese rules.


Hah, well, stakes are lower here than they were for Go Seigen I think. I’ll know for next time!


Unlike in old times when formal passes were not invented yet, in modern rules there is a simpler reason (besides L/D confirmation) why the B stone cannot surround territory.

W can force him to fill sooner or later since every W pass threatens recapture. Even if B also passes to stop the game, W can just resume, recapture and force B to use up a threat each time. (IGS goes as far as not even stopping the game before the third successive pass.)


Never have I more wished for Lasker-Maas rules so that we can get territory scoring without all this weirdness

Chinese rules are logical: it doesn’t matter if current point is your alive stone or empty point surrounded by your alive stones.
But in Japanese rules it matters. No point for your alive stone. If Black doesn’t wish to fill no matter what and white doesn’t know how to win ko fight, then… probably interpretation where it is a point is possible if both opponents agree.


This is the solution I’ve seen adopted in children’s tournaments where this kind of position is pretty common. Ref asks players if they are happy to end the game and call that a point for black. If not they continue but usually they are happy to stop and I’ve never known it make a difference to the outcome!


My position: if world is not going to fix weird bugs in rules, I would fix it myself. I would rather let opponent win than let unclear situation on board to exist. I would consider myself as a winner only if I’m ahead enough to win in any interpretation. I would fill if triple-ko happens.

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Lol, I’d totally abuse a Japanese Rules loophole if I were smart enough to do so, and if I didn’t mostly play NZD Rules anyhow

Don’t like the edge cases? Use a better ruleset imho


Go should be just area maximizing game. Without weirdness like checkmate a king.

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Without weirdness like checkmate a king.

It seems to me that chess is just a “capture the king” game. “Checkmate” just means the opponent’s king can no longer evade capture.

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Agreed; New Zealand rules are more logical (and therefore, IMO, more interesting). (EDIT: But, there are a lot more people playing Japanese on OGS, so I still play a lot of Japanese.)

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King should have right to move in coordinate where it can be captured. But I heard its not allowed in actual chess. So accidental self atari would never happen. I have no idea how they play blitz with over-complicated rules like that.

IIUC, blitz relaxes that rule.

Oh, below a certain level you can just walk your king through such fields in blitz, trust me.

But hey, once, when I left 2 total beginners unattended for 2 minutes, they managed to place 49 stones on a 7x7 board. So no rule is absolute!


but why have such rule in slow games?

I think 3 passes have been used in Dutch tournaments as well, but I think there is no written record of such small deviations from the official Japanese rules.

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