Japonese counting

kvasir · Post by **kvasir** » Sat Sep 18, 2021 7:08 am

Gérard TAILLE wrote:
$$W
$$ ---------------
$$ | . X X O . . .
$$ | O X X O . . .
$$ | X O O O . . .
$$ | X X X . . . .
$$ | . . . . . . .
$$ | . . . . . . .
Click Here To Show Diagram Code
[go]$$W $$ --------------- $$ | . X X O . . . $$ | O X X O . . . $$ | X O O O . . . $$ | X X X . . . . $$ | . . . . . . . $$ | . . . . . . .[/go]
In J89 I am not sure the result is seki (see my post viewtopic.php?p=267413#p267413 and Jann answer in viewtopic.php?p=267416#p267416)

My own understanding of j89 is that it is seki and the commentary on article 7 is correct. However, it is interesting how this position is easier to explain with a more naïve definition of life and death, that would only say that stones are alive if they can't be captured.

Snapbacks are tricky, in this case we want the territory to vanish but in many cases we want the territory to exist.

Gérard TAILLE wrote: Take this another example:
$$W white to play
$$ ---------------
$$ | . . . X O . . .
$$ | . a . X O . . .
$$ | X X X X O . . .
$$ | O O O O O . . .
$$ | . . . . . . .
$$ | . . . . . . .
Click Here To Show Diagram Code
[go]$$W white to play $$ --------------- $$ | . . . X O . . . $$ | . a . X O . . . $$ | X X X X O . . . $$ | O O O O O . . . $$ | . . . . . . . $$ | . . . . . . .[/go]
We are still in normal play with white to play.
Assume that if white plays at "a" to kill black stones then black wins the game by 0.5 point.
The only way for white to win the game is to pass, hoping black is not skillful enough to see she must add a move.
If black passes then the confirmation phase will decide black stones are dead => all corner is white territory => white wins the game
I would have prefered to say it is a seki because I do not like to see here a white territory when black can live if she plays first but it is J89 rule.

This is an example of how j89 doesn't have much useful to say about disputes. Somehow the life and death depends on rules but it is in the end up to the players to agree. By the rules, black is indeed dead but has the option to request resumption of the game and in your example he would do so and win by 0.5 point. If he does not realize this and refuses to agree that the stones are dead then both players lose because they "do not agree that the game has ended". At least this is what the commentary on article 13, clause 1 says. It is very strange how j89 allows games to end in a mutual disagreement like that, and is surely doesn't happen like that in the real world.

jann · Post by **jann** » Sat Sep 18, 2021 8:02 am

Back in the day there were some ideas to define L/D in a defender-first manner, to explain snapback without enable. I'm not sure how far anybody got with that idea though. L/D could also work in tristate: distinguish alive, dead and unsettled. This would complicate things though, so avoided as long as not necessary.

The mutual disagreement is an interesting question. I think most if not all rules phenomenon have logical explanations, it is almost never just "random tradition" that drives things.

For resumption/disagree the key point seems to be that to determine L/D, the stop position is analyzed by the players. During this they get extra/external knowledge - learn things they were not aware of during the game. If resumption would use original move order, passing first in troublesome positions could be advantageous, so pass fights could happen.

This still doesn't explain how could "both lose" though, as one side is always happy with the result of the stop position, so would agree that the game has ended. As I wrote earlier, there may be an implicit requirement here: if you say the game is finished and there are no more moves, you should have no problem letting the opponent move first in resumption even if it was he who requested it.

Gérard TAILLE · Post by **Gérard TAILLE** » Sat Sep 18, 2021 8:03 am

kvasir wrote:
Gérard TAILLE wrote:
$$W
$$ ---------------
$$ | . X X O . . .
$$ | O X X O . . .
$$ | X O O O . . .
$$ | X X X . . . .
$$ | . . . . . . .
$$ | . . . . . . .
Click Here To Show Diagram Code
[go]$$W $$ --------------- $$ | . X X O . . . $$ | O X X O . . . $$ | X O O O . . . $$ | X X X . . . . $$ | . . . . . . . $$ | . . . . . . .[/go]
In J89 I am not sure the result is seki (see my post viewtopic.php?p=267413#p267413 and Jann answer in viewtopic.php?p=267416#p267416)
My own understanding of j89 is that it is seki and the commentary on article 7 is correct. However, it is interesting how this position is easier to explain with a more naïve definition of life and death, that would only say that stones are alive if they can't be captured.

Snapbacks are tricky, in this case we want the territory to vanish but in many cases we want the territory to exist.

Gérard TAILLE wrote: Take this another example:
$$W white to play
$$ ---------------
$$ | . . . X O . . .
$$ | . a . X O . . .
$$ | X X X X O . . .
$$ | O O O O O . . .
$$ | . . . . . . .
$$ | . . . . . . .
Click Here To Show Diagram Code
[go]$$W white to play $$ --------------- $$ | . . . X O . . . $$ | . a . X O . . . $$ | X X X X O . . . $$ | O O O O O . . . $$ | . . . . . . . $$ | . . . . . . .[/go]
We are still in normal play with white to play.
Assume that if white plays at "a" to kill black stones then black wins the game by 0.5 point.
The only way for white to win the game is to pass, hoping black is not skillful enough to see she must add a move.
If black passes then the confirmation phase will decide black stones are dead => all corner is white territory => white wins the game
I would have prefered to say it is a seki because I do not like to see here a white territory when black can live if she plays first but it is J89 rule.
This is an example of how j89 doesn't have much useful to say about disputes. Somehow the life and death depends on rules but it is in the end up to the players to agree. By the rules, black is indeed dead but has the option to request resumption of the game and in your example he would do so and win by 0.5 point. If he does not realize this and refuses to agree that the stones are dead then both players lose because they "do not agree that the game has ended". At least this is what the commentary on article 13, clause 1 says. It is very strange how j89 allows games to end in a mutual disagreement like that, and is surely doesn't happen like that in the real world.

In my example I assumed white passed and I assumed also black is not skillful enough to see she must add a move in order to live => no resumption is request => confirmation phase begins.
My understanding on that point is the following : as soon as confirmation phase begins obviously you can no more request a resumption of the game because in that case
1) confirmation phase gave you more time to study the position
2) confirmation phase allowed you to study the position on another board by putting effectively on the board your sequence
3) confirmation phase allowed you to take into account the analysis of your opponent!

IOW, my point is not a resumption issue (article 13, clause 1 issue?) but a pure confirmation phase issue.

I do not see a snapback issue with J89 as it stands. Can you explain?

Cassandra · Post by **Cassandra** » Sat Sep 18, 2021 8:42 am

https://www.nihonkiin.or.jp/match/kiyak ... ku17-2.gif

jann · Post by **jann** » Sat Sep 18, 2021 9:11 am

Gérard TAILLE wrote:My understanding on that point is the following : as soon as confirmation phase begins obviously you can no more request a resumption of the game because

This is almost certainly not the case, and is likely the reason behind "resumption only requestable with opponent first" as I wrote above.

Gérard TAILLE · Post by **Gérard TAILLE** » Sat Sep 18, 2021 9:46 am

jann wrote:
Gérard TAILLE wrote:My understanding on that point is the following : as soon as confirmation phase begins obviously you can no more request a resumption of the game because
This is almost certainly not the case, and is likely the reason behind "resumption only requestable with opponent first" as I wrote above.

What do you mean Jann?

Click Here To Show Diagram Code: [go]$$W white to play $$ --------------- $$ | . . . X O . . . $$ | . a . X O . . . $$ | X X X X O . . . $$ | O O O O O . . . $$ | . . . . . . . $$ | . . . . . . .[/go]

We are still in normal play with white to play.
Assume that if white plays at "a" to kill black stones then black wins the game by 0.5 point.
1) White passes
2) Black being not skill enough passes also instead of adding a move to live and win largely the game
3) No request for resumption
4) Confirmation phase begins
5) White shows that black is dead => white wins by 0,5 point
6) Black would like to request a resumption of the game in order to win by 0,5 point if white kill black

Do the black request arrive too late? What is the final result for you?

jann · Post by **jann** » Sat Sep 18, 2021 10:05 am

Resumption is requestable, even after gaining new knowledge from confirmation. The only restriction is that you should allow the opponent to move first if you request resumption. I think this exists solely because of the new knowledge problem (and pass fight potential I mentioned above) - otherwise you wouldn't want to fiddle with move order.

See commentary on 9.3 for example. "If a game is resumed, any moves played not in accordance with the rules during the period when the game was stopped are invalid {and are presumably removed from the board. --wjh}"

This I think refers to the confirmation phase, and also moves like irregular dame fill (which btw are not necessarily part of the game under Japanese rules, only virtual moves in confirmation and/or during counting, as the text also mentions.)

Gérard TAILLE · Post by **Gérard TAILLE** » Sat Sep 18, 2021 10:19 am

jann wrote:Resumption is requestable, even after gaining new knowledge from confirmation. The only restriction is that you should allow the opponent to move first if you request resumption. I think this exists solely because of the new knowledge problem (and pass fight potential I mentioned above) - otherwise you wouldn't want to fiddle with move order.

See commentary on 9.3 for example. "If a game is resumed, any moves played not in accordance with the rules during the period when the game was stopped are invalid {and are presumably removed from the board. --wjh}"

This I think refers to the confirmation phase, and also moves like irregular dame fill (which btw are not necessarily part of the game under Japanese rules, only virtual moves in confirmation and/or during counting, as the text also mentions.)

OK Jann. That was not my first understanding but that does not sound too unreasonnable, even if the player may have gained a lot of technical analysis during confirmation phase. At least it is more fair for white to kill black instead of passing to avoid adding a move.

kvasir · Post by **kvasir** » Sat Sep 18, 2021 10:46 pm

Gérard TAILLE wrote:
In my example I assumed white passed and I assumed also black is not skillful enough to see she must add a move in order to live => no resumption is request => confirmation phase begins.
My understanding on that point is the following : as soon as confirmation phase begins obviously you can no more request a resumption of the game because in that case
1) confirmation phase gave you more time to study the position
2) confirmation phase allowed you to study the position on another board by putting effectively on the board your sequence
3) confirmation phase allowed you to take into account the analysis of your opponent!

IOW, my point is not a resumption issue (article 13, clause 1 issue?) but a pure confirmation phase issue.

I do not see a snapback issue with J89 as it stands. Can you explain?

When you assume one player has a move that gains points but doesn't want to play, then you have the solution that either player can request a resumption or they can disagree and both lose.

When I say that j89 doesn't have much useful to say about disputes I am meaning that the resolution may be adequate for informal games at the pub, but imagine disagreeing like I described in a tournament game. It seems unreasonable how j89 handles disputes and even something as simple as colluding to score the game incorrectly.

Basically, I just don't think everything in j89 can be taken seriously, it is just that when you assume j89 rules and specific problem it is not so clear what to ignore or treat differently then stated in j89. The articles about both losing, forfeiting the game, and so on all serve a purpose to eliminate loose ends, but not actually to create practical rules for competitive play.

About snapback issues. I am not sure there are snapback issues in j89 except that the arguments used to determine some positions with snapbacks can be unintuitive, tricky and not convincing to everyone...that is just a perspective.

Gérard TAILLE · Post by **Gérard TAILLE** » Sun Sep 19, 2021 6:54 am

Where are we concerning the interpretation of pass-for-ko rule?

J89 pass-each-time: ko pass needed each time.
This is the traditional interpretation of the rule but obvioulsly a big flaw exists here with all positions with double ko. I do not know if it is an overlooked problem or if it is translation issue but for me this interpretation causes too many problems.

J89 pass-once: ko pass for first recapture only.
Jann highlighted this other interpretation of the rule. This interpretation is very interesting because the identified flaw of the double ko is now solved, at least for all examples given in the rule => that looks a very strong argument in favor of this interpretation.

My proposal : in order to avoid mentionning continuously this big flaw in J89 pass-each-time can't we agree to say that the correct interpretation is really this J89 pass-once with a ko pass required only for the first recapture?

That does not mean that J89 pass-once is flawless but at least it is consistent with all examples with double ko, given in the rule.

The number of remaining flaws are now very small indeed. Basically I identified three positions and in each of them the problem is due to the presence of a double ko.
These positions are the following:

Click Here To Show Diagram Code: [go]$$B $$ --------------------- $$ | O . O . X . . O . . $$ | O O O X O X O O . . $$ | X X X O . O . . . . $$ | . . . O O O . . . . $$ | . . . . . . . . . . $$ | . . . . . . . . . . $$ | . . . . . . . . . . $$ -----------------[/go]

Click Here To Show Diagram Code: [go]$$B $$ ----------------- $$ | O X . X . O . | $$ | . O X X X O O | $$ | O . O O X X O | $$ | O O O . O X O | $$ | X X O O X X O | $$ | . X X O O O . | $$ | X . X X X O O | $$ -----------------[/go]

edit:

Click Here To Show Diagram Code: [go]$$B $$ +---------------------–- $$ | . X X O X O . . . O X O . O . | $$ | X O . O X O . . . O X X O O O | $$ | O O X X X O . . . O X . X O X | $$ | O X X O O O . . . O X X X X . | $$ | . O X O . . . . . O O O O X X | $$ | a O X O . . . . . . . . O O O | $$ | O X X O . . . . . . . . . . . | $$ | O O O O . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . |[/go]

In the first two positions the problem is due to an unexpected required pass-for-ko in a double ko.
In the third position the problem is due to the pass-for-ko required only ONCE (in this example if you require a pass-for-ko for the TWO first ko captures then the problem disappears).

I believe I have discovered a modification of the pass-for-ko rule to solved all these reamining issues but first of all I would like to ask you if you know other positions which could be an issue for this J89 pass-once.

jann · Post by **jann** » Sun Sep 19, 2021 11:13 am

Gérard TAILLE wrote:My proposal : in order to avoid mentionning continuously this big flaw in J89 pass-each-time can't we agree to say that the correct interpretation is really this J89 pass-once with a ko pass required only for the first recapture?

The closed loop in double kos was never a thing, this is clear from the examples. The question is only about whether whether this only a precedential ruling/restriction at the moment (and subject of a slight rule correction in the future), or whether J89 already has a good logical explanation for that.

At the moment I'm 75% sure that pass-once is the official J89 rule. The commentary mentioned here spells this out almost literally (after passing for it, the ko becomes like if the game resumed - and no pass-for-ko required in resumption).

Another reason I feel more and more confident is the amount of noticeable work went into J89. Have you seen the official Korean or Chinese rules (or many other for that matter)? The richness of J89 commentary, the number of L/D examples and all the different aspects of L/D they examine show that J89 is the result of a lot of work and attention. It's hard to imagine such an obvious double ko flaw could have remained unnoticed (though the older version also had a few gross errors in comments and an example which may contradict this - maybe they came from different editors or so?).

The number of remaining flaws are now very small indeed. Basically I identified three positions and in each of them the problem is due to the presence of a double ko.
These positions are the following:

You may want to dig through some old bestiaries. There were an original pass-for-ko counterexample a few decades ago. I don't clearly remember now but it was a relatively large position (9x9 or bigger) and it also demonstrated an unnecessary reinforcement move.

Also note ligtvector's example (which I considered the biggest flaw of J89) does not work, as kvasir noticed:

$$B
$$ ---------------------
$$ | O . O . X . . O . .
$$ | O O O X O X O O . .
$$ | X X X O . O . . . .
$$ | . . . O O O . . . .
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .
$$ -----------------
Click Here To Show Diagram Code
[go]$$B $$ --------------------- $$ | O . O . X . . O . . $$ | O O O X O X O O . . $$ | X X X O . O . . . . $$ | . . . O O O . . . . $$ | . . . . . . . . . . $$ | . . . . . . . . . . $$ | . . . . . . . . . . $$ -----------------[/go]

B cannot seem to do anything to the corner without capturing a W stone in the ko first, and this stone will be replayed and become uncapturable, so is an enabled stone.

In the third position the problem is due to the pass-for-ko required only ONCE (in this example if you require a pass-for-ko for the TWO first ko captures then the problem disappears).

That doesn't sood like a good idea. Note that pass-once has a good theoretical rationale as is (freeze and simplify the dynamics related to the stop position, and let a pass for it "resume the game" there). Pass-twice sounds ad-hoc without any theory ground.

I also don't see a serious problem in your third example - the behavior will remain reasonable and any difference to pass-each-time is irrelevant if that is not the official rule. Maybe a single email to the Nihon Ki-in could answer the question.

Gérard TAILLE · Post by **Gérard TAILLE** » Sun Sep 19, 2021 11:32 am

jann wrote:
Gérard TAILLE wrote:My proposal : in order to avoid mentionning continuously this big flaw in J89 pass-each-time can't we agree to say that the correct interpretation is really this J89 pass-once with a ko pass required only for the first recapture?
The closed loop in double kos was never a thing, this is clear from the examples. The question is only about whether whether this only a precedential ruling/restriction at the moment (and subject of a slight rule correction in the future), or whether J89 already has a good logical explanation for that.

At the moment I'm 75% sure that pass-once is the official J89 rule. The commentary mentioned here spells this out almost literally (after passing for it, the ko becomes like if the game resumed - and no pass-for-ko required in resumption).

Another reason I feel more and more confident is the amount of noticeable work went into J89. Have you seen the official Korean or Chinese rules (or many other for that matter)? The richness of J89 commentary, the number of L/D examples and all the different aspects of L/D they examine show that J89 is the result of a lot of work and attention. It's hard to imagine such an obvious double ko flaw could have remained unnoticed (though the older version had a few gross errors in comments which may contradict this - maybe they came from different editors or so?).

The number of remaining flaws are now very small indeed. Basically I identified three positions and in each of them the problem is due to the presence of a double ko.
These positions are the following:
You may want to dig through some old bestiaries. There were an original pass-for-ko counterexample a few decades ago. I don't clearly remember now but it was a relatively large position (9x9 or bigger) and it also demonstrated an unnecessary reinforcement move.

Also note ligtvector's example (which I considered the biggest flaw of J89) does not work, as kvasir noticed:

$$B
$$ ---------------------
$$ | O . O . X . . O . .
$$ | O O O X O X O O . .
$$ | X X X O . O . . . .
$$ | . . . O O O . . . .
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .
$$ -----------------
Click Here To Show Diagram Code
[go]$$B $$ --------------------- $$ | O . O . X . . O . . $$ | O O O X O X O O . . $$ | X X X O . O . . . . $$ | . . . O O O . . . . $$ | . . . . . . . . . . $$ | . . . . . . . . . . $$ | . . . . . . . . . . $$ -----------------[/go]
B cannot seem to do anything to the corner without capturing a W stone in the ko first, and this stone will be replayed and become uncapturable, so is an enabled stone.

In the third position the problem is due to the pass-for-ko required only ONCE (in this example if you require a pass-for-ko for the TWO first ko captures then the problem disappears).
That doesn't sood like a good idea. Note that pass-once has a good theoretical rationale as is (freeze and simplify the dynamics related to the stop position, and let a pass for it "resume the game" there). Pass-twice sounds ad-hoc without any theory ground.

Click Here To Show Diagram Code: [go]$$B $$ ---------------------- $$ | P . P . Z . . O O . O $$ | P P P Z O Z O O O O O $$ | X X X O . O O . O . . $$ | X . X O O O O O . . . $$ | . X X . . . . . . . . $$ | X X . . . . . . . . . $$ | . . . . . . . . . . . $$ | . . . . . . . . . . .[/go]

see https://www.lifein19x19.com/viewtopic.p ... 51#p267451. It looks the result is seki but I am not quite sure.

jann · Post by **jann** » Sun Sep 19, 2021 11:35 am

I doubt a new permanent stone UNDER a captured one could ever be anything but enabled, neither that there is any restriction about where to look for enabled stones.

Gérard TAILLE · Post by **Gérard TAILLE** » Sun Sep 19, 2021 1:11 pm

jann wrote:I doubt a new permanent stone UNDER a captured one could ever be anything but enabled, neither that there is any restriction about where to look for enabled stones.

Black to play : the result for white is the following

Click Here To Show Diagram Code: [go]$$W $$ ---------------------- $$ | . X . X X W C W W C W $$ | . . . X W C W W W W W $$ | X X X W C W W C W . . $$ | X . X W W W W W . . . $$ | . X X . . . . . . . . $$ | X X . . . . . . . . . $$ | . . . . . . . . . . . $$ | . . . . . . . . . . .[/go]

My understanding is that all the area contolled here by white is not due to the capture of the five white stones in the corner. It is white area in ANY CASE. I do see a white stone captured by black and then a white permanent stone under the captured one but I do not see a NEW permanent stone. It just like a nakade : the stone can be captured, is reestablished but is it a NEW permanent stone?

jann · Post by **jann** » Sun Sep 19, 2021 1:19 pm

Compare to snapback. No change in area, the reason the original stone is alive is solely because a new one played under the original IS enabled by the capture.

Life In 19x19

Japonese counting

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