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 Post subject: Re: Japonese counting
Post #321 Posted: Fri Sep 17, 2021 8:11 am 
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kvasir wrote:
I think I said something similar few posts ago, but like you pointed out it is not at all clear what new stones count in this case.

In example 2 it is claimed that the new stones at :b1: and :b3: make the black marked stones alive.
Click Here To Show Diagram Code
[go]$$B
$$ ----------------
$$ | 4 Y O 1 O X .
$$ | Y 2 O 3 O X .
$$ | O O O O X X .
$$ | X X X X . . .
$$ | . . . . . . .[/go]


Click Here To Show Diagram Code
[go]$$B
$$ ----------------
$$ | . X O 1 O X .
$$ | X . O 2 O X .
$$ | O O O O X X .
$$ | X X X X . . .
$$ | . . . . . . .[/go]

On :b1: white must play this :w2: and I do not see how black can force new stones.

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 Post subject: Re: Japonese counting
Post #322 Posted: Fri Sep 17, 2021 8:15 am 
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Gérard TAILLE wrote:
kvasir wrote:
I think I said something similar few posts ago, but like you pointed out it is not at all clear what new stones count in this case.

In example 2 it is claimed that the new stones at :b1: and :b3: make the black marked stones alive.
Click Here To Show Diagram Code
[go]$$B
$$ ----------------
$$ | 4 Y O 1 O X .
$$ | Y 2 O 3 O X .
$$ | O O O O X X .
$$ | X X X X . . .
$$ | . . . . . . .[/go]


Click Here To Show Diagram Code
[go]$$B
$$ ----------------
$$ | . X O 1 O X .
$$ | X . O 2 O X .
$$ | O O O O X X .
$$ | X X X X . . .
$$ | . . . . . . .[/go]

On :b1: white must play this :w2: and I do not see how black can force new stones.


Sorry, I misquoted the diagram. It is supposed to be white trying to capture the black stones. That is show that white can not capture the 2 stones without black being able to play new stones.

Click Here To Show Diagram Code
[go]$$W
$$ ----------------
$$ | 3 X O 2 O X .
$$ | X 1 O 4 O X .
$$ | O O O O X X .
$$ | X X X X . . .
$$ | . . . . . . .[/go]

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 Post subject: Re: Japonese counting
Post #323 Posted: Fri Sep 17, 2021 8:22 am 
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kvasir wrote:
Gérard TAILLE wrote:
kvasir wrote:
I think I said something similar few posts ago, but like you pointed out it is not at all clear what new stones count in this case.

In example 2 it is claimed that the new stones at :b1: and :b3: make the black marked stones alive.
Click Here To Show Diagram Code
[go]$$B
$$ ----------------
$$ | 4 Y O 1 O X .
$$ | Y 2 O 3 O X .
$$ | O O O O X X .
$$ | X X X X . . .
$$ | . . . . . . .[/go]


Click Here To Show Diagram Code
[go]$$B
$$ ----------------
$$ | . X O 1 O X .
$$ | X . O 2 O X .
$$ | O O O O X X .
$$ | X X X X . . .
$$ | . . . . . . .[/go]

On :b1: white must play this :w2: and I do not see how black can force new stones.


Sorry, I misquoted the diagram. It is supposed to be white trying to capture the black stones. That is show that white can not capture the 2 stones without black being able to play new stones.

Click Here To Show Diagram Code
[go]$$W
$$ ----------------
$$ | 3 X O 2 O X .
$$ | X 1 O 4 O X .
$$ | O O O O X X .
$$ | X X X X . . .
$$ | . . . . . . .[/go]


yes I agree but how this sequence may impact another other part of the board? Neither white nor black can force a new stone.
IOW if white wants to kill a black group of stones somewhere else on the board then white has only to avoid playing this :w1: here and black will not be able to claim she has got a new stone.

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 Post subject: Re: Japonese counting
Post #324 Posted: Fri Sep 17, 2021 8:35 am 
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Click Here To Show Diagram Code
[go]$$W
$$ ----------------
$$ | . X O . O X .
$$ | X . O a O X .
$$ | O O O O X X .
$$ | X X X X . . .
$$ | . . . . . . .[/go]


BTW this position looks an unfinished position:
In this position black has a big ko threat at "a". OC it is not an "ideal" ko threat because using it cost black one point (a captured stone) but it is anyway a possibility for black.
In normal play, as soon as temperature drops under 6 it is good practice for white to play:
Click Here To Show Diagram Code
[go]$$W
$$ ----------------
$$ | 3 X O 4 O X .
$$ | X 1 O 2 O X .
$$ | O O O O X X .
$$ | X X X X . . .
$$ | . . . . . . .[/go]


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

In the resulting position black has lost her big ko-threat and white has gained a small but ideal ko threat at "a".

For that reason the initial position is in practice an unfinished position.

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 Post subject: Re: Japonese counting
Post #325 Posted: Fri Sep 17, 2021 7:15 pm 
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It is interesting to consider such positions.

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


The pattern is to leave one liberty for white and an eye for black.

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


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


We can also make it work when white needs three moves to capture on the inside using a ko.

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


We can also think of positions in which black has a chance to fight the ko because white is behind in the race to capture.

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


White in confirmation.

Click Here To Show Diagram Code
[go]$$W
$$ ----------------
$$ | 1 X X X X X X X X X X X 5 X . X X O O O X .
$$ | X O 3 O O O O O O O O O X X X X O 2 4 O X .
$$ | O O O O O O O O O O O O O O O O O O O X X .
$$ | X X X X X X X X X X X X X X X X X X X .
$$ | . . . . . . .[/go]


Black in confirmation
Click Here To Show Diagram Code
[go]$$B
$$ ----------------
$$ | . X X X X X X X X X X X . X . X X O O O X .
$$ | X O . O O O O O O O O O X X X X O 1 2 O X .
$$ | O O O O O O O O O O O O O O O O O O O X X .
$$ | X X X X X X X X X X X X X X X X X X X .
$$ | . . . . . . .[/go]


The reason black may not want to give a prisoner is he may defend with a ko, so he can save 1pt by not throwing in at :b2:

Click Here To Show Diagram Code
[go]$$W :b4: ko threat
$$ ----------------
$$ | 3 X X X X X X X X X X X . X . X X O O O X .
$$ | X O 1 O O O O O O O O O X X X X O 2 . O X .
$$ | O O O O O O O O O O O O O O O O O O O X X .
$$ | X X X X X X X X X X X X X X X X X X X .
$$ | . . . . . . .[/go]



j89 example 2 explains why these positions are seki by stating that new stones can be played. It seem more intuitive to think of it as unfinished or unsettled positions and therefore seki when you count the game, maybe this is the intent of the definition of life and death in article 7.1 and territory in 8. ? If that is the case, people may disagree if it is a good idea to avoid the intuitive explanation altogether when presenting the rules. The benefit of referring to the idea of unsettled stones is that it gives guidance as to how to read the rules and it could also explains quite nicely why there is no territory in seki. On the other had it is quite a lofty idea that is hard to define and one could say unnecessary.

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 Post subject: Re: Japonese counting
Post #326 Posted: Fri Sep 17, 2021 8:00 pm 
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kvasir wrote:
j89 example 2 explains why these positions are seki by stating that new stones can be played. It seem more intuitive to think of it as unfinished or unsettled positions and therefore seki when you count the game, maybe this is the intent of the definition of life and death in article 7.1 and territory in 8. ?

I dont think so. The exchange can be neutral, favorable or unfavorable (then the position is settled):

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

But L/D is static, it cannot evaluate exchanges. It must assume any exchange is unfavorable (thus unacceptable). You don't need to give up ("enable") any kind of compensation to be able to capture dead stones from your territory - if you need to then those are not really dead stones.

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 Post subject: Re: Japonese counting
Post #327 Posted: Fri Sep 17, 2021 8:57 pm 
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jann wrote:
kvasir wrote:
j89 example 2 explains why these positions are seki by stating that new stones can be played. It seem more intuitive to think of it as unfinished or unsettled positions and therefore seki when you count the game, maybe this is the intent of the definition of life and death in article 7.1 and territory in 8. ?

I dont think so. The exchange can be neutral, favorable or unfavorable (then the position is settled):

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

But L/D is static, it cannot evaluate exchanges. It must assume any exchange is unfavorable (thus unacceptable). You don't need to give up ("enable") any kind of compensation to be able to capture dead stones from your territory - if you need to then those are not really dead stones.


I don't mean unsettled as in "undecided", I think I pointed out also that one might get into trouble if one tries to define "unsettled" precisely, but I am referring to the way that it is necessary to argue that these stones are alive because capturing them would alter the life and death of other stones.

I completely agree with you that the life and death needs to be a static property when the game ends.

I don't want to get into semantics but "settled" has a meaning of "place so as to stay" in my dictionary, so unsettled can mean something was done the opposite: placed though it could not stay. I think that describes what I meant very well.

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 Post subject: Re: Japonese counting
Post #328 Posted: Sat Sep 18, 2021 2:49 am 
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For sure the rule has not to define what is an unfinished or unsettled position. This wording belongs to the go player but not to the rule.
The rule must give the result for any position but for unfinished position a large range of values might be acceptable because it will not change the game itself and the final result.

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

In this unfinished position the final expected result is : white plays first and the local result is -2 (four black prisonners against two white prisonners).
As a consequence if the rule gives for this unfinished position a result greater or equal to -2 then everything is OK and the expected result will be reached.
=> it does not matter is you decide the result is 0 (seki?) or +1 (white marked stone is dead will black stones are alive)

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 Post subject: Re: Japonese counting
Post #329 Posted: Sat Sep 18, 2021 3:48 am 
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Gérard TAILLE wrote:
For sure the rule has not to define what is an unfinished or unsettled position. This wording belongs to the go player but not to the rule.
The rule must give the result for any position but for unfinished position a large range of values might be acceptable because it will not change the game itself and the final result.

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

In this unfinished position the final expected result is : white plays first and the local result is -2 (four black prisonners against two white prisonners).
As a consequence if the rule gives for this unfinished position a result greater or equal to -2 then everything is OK and the expected result will be reached.
=> it does not matter is you decide the result is 0 (seki?) or +1 (white marked stone is dead will black stones are alive)



But wait a minute, this is a non-sequitur, because white loses points by not resolving this before the end of the game and the value of resolving the position is either 1 or 2 pts. depending on ko threats. I think "zero" is a very special number here, it is the only value you can assign without getting into the details of which side benefits by playing first. So I would say it does matter what value you try to assign.

Let me be clear, I was not suggesting that the rules NEED to define what an unsettled position is but that the combinations of rules can INTUTIVELY be understood to be assigning zero territory in unsettled positions.

So yes, it is seki if left as is but before the end of the game it depends on ko threats but white will gain 1 or 2 points even if he can't win a ko as long as he resolves this before the end of the game.

Click Here To Show Diagram Code
[go]$$W
$$ ---------------
$$ | 1 X X O . . .
$$ | O X X O . . .
$$ | X O O O . . .
$$ | X X X . . . .
$$ | . . . . . . .
$$ | . . . . . . .[/go]



Click Here To Show Diagram Code
[go]$$ B
$$ ---------------
$$ | O 2 3 O . . .
$$ | O 1 . O . . .
$$ | X O O O . . .
$$ | X X X . . . .
$$ | . . . . . . .
$$ | . . . . . . .[/go]


Now if black does not wish to fight a ko it is w+2 because it is 5 black prisoners and 3 white.

Click Here To Show Diagram Code
[go]$$W
$$ ---------------
$$ | . 3 X O . . .
$$ | 2 X 1 O . . .
$$ | X O O O . . .
$$ | X X X . . . .
$$ | . . . . . . .
$$ | . . . . . . .[/go]


If black wishes he can create a ko shape and try to connect everything which is w+1.

Click Here To Show Diagram Code
[go]$$W
$$ ---------------
$$ | 2 . X O . . .
$$ | . X 1 O . . .
$$ | X O O O . . .
$$ | X X X . . . .
$$ | . . . . . . .
$$ | . . . . . . .[/go]

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 Post subject: Re: Japonese counting
Post #330 Posted: Sat Sep 18, 2021 5:42 am 
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kvasir wrote:
Gérard TAILLE wrote:
For sure the rule has not to define what is an unfinished or unsettled position. This wording belongs to the go player but not to the rule.
The rule must give the result for any position but for unfinished position a large range of values might be acceptable because it will not change the game itself and the final result.

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

In this unfinished position the final expected result is : white plays first and the local result is -2 (four black prisonners against two white prisonners).
As a consequence if the rule gives for this unfinished position a result greater or equal to -2 then everything is OK and the expected result will be reached.
=> it does not matter is you decide the result is 0 (seki?) or +1 (white marked stone is dead will black stones are alive)



But wait a minute, this is a non-sequitur, because white loses points by not resolving this before the end of the game and the value of resolving the position is either 1 or 2 pts. depending on ko threats. I think "zero" is a very special number here, it is the only value you can assign without getting into the details of which side benefits by playing first. So I would say it does matter what value you try to assign.

Let me be clear, I was not suggesting that the rules NEED to define what an unsettled position is but that the combinations of rules can INTUTIVELY be understood to be assigning zero territory in unsettled positions.

So yes, it is seki if left as is but before the end of the game it depends on ko threats but white will gain 1 or 2 points even if he can't win a ko as long as he resolves this before the end of the game.

Click Here To Show Diagram Code
[go]$$W
$$ ---------------
$$ | 1 X X O . . .
$$ | O X X O . . .
$$ | X O O O . . .
$$ | X X X . . . .
$$ | . . . . . . .
$$ | . . . . . . .[/go]



Click Here To Show Diagram Code
[go]$$ B
$$ ---------------
$$ | O 2 3 O . . .
$$ | O 1 . O . . .
$$ | X O O O . . .
$$ | X X X . . . .
$$ | . . . . . . .
$$ | . . . . . . .[/go]


Now if black does not wish to fight a ko it is w+2 because it is 5 black prisoners and 3 white.

Click Here To Show Diagram Code
[go]$$W
$$ ---------------
$$ | . 3 X O . . .
$$ | 2 X 1 O . . .
$$ | X O O O . . .
$$ | X X X . . . .
$$ | . . . . . . .
$$ | . . . . . . .[/go]


If black wishes he can create a ko shape and try to connect everything which is w+1.

Click Here To Show Diagram Code
[go]$$W
$$ ---------------
$$ | 2 . X O . . .
$$ | . X 1 O . . .
$$ | X O O O . . .
$$ | X X X . . . .
$$ | . . . . . . .
$$ | . . . . . . .[/go]


Assigning zero territory in unsettled positions seems logical to me and it is the case with "GT territory rule". :)
But in J89 as it stands it is not the case. ;-)

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 https://lifein19x19.com/viewtopic.php?p=267413#p267413 and Jann answer in https://lifein19x19.com/viewtopic.php?p=267416#p267416)


Take this another example:
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.

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 Post subject: Re: Japonese counting
Post #331 Posted: Sat Sep 18, 2021 7:08 am 
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Gérard TAILLE wrote:
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 https://lifein19x19.com/viewtopic.php?p=267413#p267413 and Jann answer in https://lifein19x19.com/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:
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.

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 Post subject: Re: Japonese counting
Post #332 Posted: Sat Sep 18, 2021 8:02 am 
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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.


Last edited by jann on Sat Sep 18, 2021 9:16 am, edited 2 times in total.
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 Post subject: Re: Japonese counting
Post #333 Posted: Sat Sep 18, 2021 8:03 am 
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kvasir wrote:
Gérard TAILLE wrote:
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 https://lifein19x19.com/viewtopic.php?p=267413#p267413 and Jann answer in https://lifein19x19.com/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:
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?

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Post #334 Posted: Sat Sep 18, 2021 8:42 am 
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 Post subject: Re: Japonese counting
Post #335 Posted: Sat Sep 18, 2021 9:11 am 
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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.

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Post #336 Posted: Sat Sep 18, 2021 9:46 am 
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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?

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 Post subject: Re: Japonese counting
Post #337 Posted: Sat Sep 18, 2021 10:05 am 
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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.)

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Post #338 Posted: Sat Sep 18, 2021 10:19 am 
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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.

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 Post subject: Re: Japonese counting
Post #339 Posted: Sat Sep 18, 2021 10:46 pm 
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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.

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 Post subject: Re: Japonese counting
Post #340 Posted: Sun Sep 19, 2021 6:54 am 
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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.

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