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 Post subject: Re: Japonese counting
Post #301 Posted: Tue Sep 14, 2021 10:37 am 
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Gérard TAILLE wrote:
kvasir wrote:
Cassandra wrote:
Click Here To Show Diagram Code
[go]$$B :b7: pass-for-ko
$$ | . . . . . . .
$$ | . . . . . . .
$$ | O O O O O O .
$$ | . . . . . O .
$$ | X X X X . O .
$$ | X 4 6 . . O .
$$ | X O O O O O .
$$ | X X O O O . .
$$ | X X X X O . .
$$ | 5 X O X O . .
$$ | X O . O X . .
$$ | O O O O X . .
$$ | . O X X X . .
$$ | O O X . . . .
$$ | X X X . . . .
$$ | . . . . . . .[/go]


Obviously, black has time to connect. Me not thinking :scratch:

In the above position the white group is alive because :w4: and :w6: are in the "enable" region (in J2003 they are in local2)

:lol: :lol: :lol:

Where and how is "enable region" defined in J89?

You may occupy DAME, whenever you like.
I don't think that such moves are a proper means in Japanese understanding to bring anything captured back to life.

However, may it be as you like.
Even if Black was judged to be more than dead, he would request resumption of the game. As with every other semeai on the board that has not been played out until the very end.

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 Post subject: Re: Japonese counting
Post #302 Posted: Tue Sep 14, 2021 11:21 am 
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Gérard TAILLE wrote:
In the above position the white group is alive because :w4: and :w6: are in the "enable" region (in J2003 they are in local2)


I will try to think about the other points you made tomorrow, but I think you are mistaken that :w4: and :w6: in local-2.

The j89 text basically says very little about what are reestablished stones, which is a general problem with j89. However, I don't think it is correct to say :w4: and :w6: are in local-2 because while that is true, it is almost a tautology since these new stones can't be captured because they are part of one of the outside groups, they are not in the RIGHT local-2. Robert uses the word "recursively" in his definition without actually defining what he means, I think I know what he means but maybe this is where you missed the point. :w4: and :w6: are separate from the the intersections that are captured by intersections that have the other color. That is every path between :w4: and :w6: and the captured stones has one or more black stones, that is in the games final position - not any position resulting from capturing these stones.

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 Post subject: Re: Japonese counting
Post #303 Posted: Tue Sep 14, 2021 12:09 pm 
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kvasir wrote:
Gérard TAILLE wrote:
In the above position the white group is alive because :w4: and :w6: are in the "enable" region (in J2003 they are in local2)


I will try to think about the other points you made tomorrow, but I think you are mistaken that :w4: and :w6: in local-2.

The j89 text basically says very little about what are reestablished stones, which is a general problem with j89. However, I don't think it is correct to say :w4: and :w6: are in local-2 because while that is true, it is almost a tautology since these new stones can't be captured because they are part of one of the outside groups, they are not in the RIGHT local-2. Robert uses the word "recursively" in his definition without actually defining what he means, I think I know what he means but maybe this is where you missed the point. :w4: and :w6: are separate from the the intersections that are captured by intersections that have the other color. That is every path between :w4: and :w6: and the captured stones has one or more black stones, that is in the games final position - not any position resulting from capturing these stones.


Because nobody knows exactly what means "enable" you are certainly right but I may also be right ;-)
In anycase, it does not matter if it is in "eanble" region or if it is simply dame, the result is a seki isn't it?

Coming back to your proposal can you clarify what are the results of your confirmation phase with Position 1 and Position 2?

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 Post subject: Re: Japonese counting
Post #304 Posted: Tue Sep 14, 2021 8:21 pm 
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Using what I understand of j89 .

Click Here To Show Diagram Code
[go]$$B Position 1
$$ | . . . . . . .
$$ | O O . . . . .
$$ | . O . . . . .
$$ | Z O . . . . .
$$ | S X O O O . .
$$ | X X X X O . .
$$ | P X S X O . .
$$ | S O Z O X . .
$$ | O O O O X . .
$$ | . O X X X . .
$$ | O O X . . . .
$$ | X X X . . . .
$$ | . . . . . . .[/go]



I think we may declare this seki in j89 because the marked stones are dead, and the boxes are dame by j89. As usual it is murky water.

Click Here To Show Diagram Code
[go]$$B Position 2
$$ | . . . . . . .
$$ | . . . . . . .
$$ | O O O O O O .
$$ | S S S S S O .
$$ | X X X X S O .
$$ | X S S S S O .
$$ | X O O O O O .
$$ | . X O O O . .
$$ | X X X X O . .
$$ | P X . X O . .
$$ | . P X P X . .
$$ | P P P P X . .
$$ | . P X X X . .
$$ | P P X . . . .
$$ | X X X . . . .
$$ | . . . . . . .[/go]


This one is more troublesome. On the face of it is seki, because while the marked stones are dead which makes black alive there is dame on the squares. This would seem to match the examples, they disallow filling in such cases.


In both cases I think it is implicit that this is a result of an "irregularity", one or both player have refused to play some moves, it would be better to treat it as such. J89 and many other rules just don't have much useful to say about irregularities. It is another discussion, but it allows one to ask questions about such irregular positions. I think the intention of J89 on irregular positions is that if the stones can't be shown to be capturable then they remain on the board, then the rule for territory should be applied to score the game. It just gets into lot of murky waters when you try to apply the same kind of logic as used to handle some tricky but legitimate positions.

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 Post subject: Re: Japonese counting
Post #305 Posted: Wed Sep 15, 2021 2:59 am 
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By the way:
James Davies' translation of J89's Article 8 was not very accurate.

Article 8 says:

The empty points surrounded by only one player's live stones are called "eyes",
and the empty points other than the eyes are called "useless points"1).
Live stones that have useless points are called "seki stones",
and the eyes of live stones other than seki stones are called "territory".
One point2) of the territory is called "one point3)".

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1) aka "dame"
2) physical relation to the board
3) related to scoring


This makes evident that the formations that were discussed above, are NO seki; they only contain "seki stones".
A "seki" as such is NOT mentioned in the legal text of J89.

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 Post subject: Re: Japonese counting
Post #306 Posted: Thu Sep 16, 2021 8:22 am 
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kvasir wrote:
Using what I understand of j89 .

Click Here To Show Diagram Code
[go]$$B Position 1
$$ | . . . . . . .
$$ | O O . . . . .
$$ | . O . . . . .
$$ | Z O . . . . .
$$ | S X O O O . .
$$ | X X X X O . .
$$ | P X S X O . .
$$ | S O Z O X . .
$$ | O O O O X . .
$$ | . O X X X . .
$$ | O O X . . . .
$$ | X X X . . . .
$$ | . . . . . . .[/go]



I think we may declare this seki in j89 because the marked stones are dead, and the boxes are dame by j89. As usual it is murky water.

Click Here To Show Diagram Code
[go]$$B Position 2
$$ | . . . . . . .
$$ | . . . . . . .
$$ | O O O O O O .
$$ | S S S S S O .
$$ | X X X X S O .
$$ | X S S S S O .
$$ | X O O O O O .
$$ | . X O O O . .
$$ | X X X X O . .
$$ | P X . X O . .
$$ | . P X P X . .
$$ | P P P P X . .
$$ | . P X X X . .
$$ | P P X . . . .
$$ | X X X . . . .
$$ | . . . . . . .[/go]


This one is more troublesome. On the face of it is seki, because while the marked stones are dead which makes black alive there is dame on the squares. This would seem to match the examples, they disallow filling in such cases.


In both cases I think it is implicit that this is a result of an "irregularity", one or both player have refused to play some moves, it would be better to treat it as such. J89 and many other rules just don't have much useful to say about irregularities. It is another discussion, but it allows one to ask questions about such irregular positions. I think the intention of J89 on irregular positions is that if the stones can't be shown to be capturable then they remain on the board, then the rule for territory should be applied to score the game. It just gets into lot of murky waters when you try to apply the same kind of logic as used to handle some tricky but legitimate positions.


I order to reach the seki result I can see you prefer using the "dame" rather than "enable".
We all know that "enable" is not defined but at least is it possible to understand what is the "intention" on a basic example.

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


OC, we know this position is unfinished and we know also that the final result of normal play will be in general:
Click Here To Show Diagram Code
[go]$$B Diag 1
$$ ---------------
$$ | B W W O . . .
$$ | B B W O . . .
$$ | X O O O . . .
$$ | X X X . . . .
$$ | . . . . . . .
$$ | . . . . . . .[/go]


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

Now how do you proceed with the confirmation phase to know the status of :wc: ?
No doubt :wc: is capturable.
Has white the possibility to put some stones that the opponent could not capture? Yes no doubt here also. But are these stones "NEW" stones that the opponent could not capture? Here is the problem because looking at Diag 1 these NEW stones are not really new and are the normal result, independently of who plays first.

BTW, even if the result is not seki it does not really harm because in any case the position is unfinished :)
What is your understanding of "enable a NEW stone" in this example?

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 Post subject: Re: Japonese counting
Post #307 Posted: Thu Sep 16, 2021 9:53 am 
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kvasir wrote:
Click Here To Show Diagram Code
[go]$$B Position 1
$$ | . . . . . . .
$$ | O O . . . . .
$$ | . O . . . . .
$$ | Z O . . . . .
$$ | S X O O O . .
$$ | X X X X O . .
$$ | P X S X O . .
$$ | S O Z O X . .
$$ | O O O O X . .
$$ | . O X X X . .
$$ | O O X . . . .
$$ | X X X . . . .
$$ | . . . . . . .[/go]

I think we may declare this seki in j89 because the marked stones are dead, and the boxes are dame by j89.

I don't see why, B looks outright dead in J89 and all W inside alive thus no dame.

(Maybe you meant the closed pass-for-ko loop? But that would break most examples and we can safely assume is not allowed, the only question is why and how but that seems irrelevant here.)

Gérard TAILLE wrote:
We all know that "enable" is not defined but at least is it possible to understand what is the "intention" on a basic example.

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

I think enable is not that bad at all, just the commentary for this example is incorrect. Even its text shows (both lines, except maybe 1-2 moves at the end) that W can play the key 2 stones (that the commentary refer to as "enabled") regardless of who plays first, and seems he can also play them even if B solely focus on preventing them ignoring anything else. W stone is dead.

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 Post subject: Re: Japonese counting
Post #308 Posted: Thu Sep 16, 2021 11:12 am 
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jann wrote:
kvasir wrote:
Click Here To Show Diagram Code
[go]$$B Position 1
$$ | . . . . . . .
$$ | O O . . . . .
$$ | . O . . . . .
$$ | Z O . . . . .
$$ | S X O O O . .
$$ | X X X X O . .
$$ | P X S X O . .
$$ | S O Z O X . .
$$ | O O O O X . .
$$ | . O X X X . .
$$ | O O X . . . .
$$ | X X X . . . .
$$ | . . . . . . .[/go]

I think we may declare this seki in j89 because the marked stones are dead, and the boxes are dame by j89.

I don't see why, B looks outright dead in J89 and all W inside alive thus no dame.

(Maybe you meant the closed pass-for-ko loop? But that would break most examples and we can safely assume is not allowed, the only question is why and how but that seems irrelevant here.)

Gérard TAILLE wrote:
We all know that "enable" is not defined but at least is it possible to understand what is the "intention" on a basic example.

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

I think enable is not that bad at all, just the commentary for this example is incorrect. Even its text shows (both lines, except maybe 1-2 moves at the end) that W can play the key 2 stones (that the commentary refer to as "enabled") regardless of who plays first, and seems he can also play them even if B solely focus on preventing them ignoring anything else. W stone is dead.


What about the four black stones? Are they also dead? IOW is it different if the NEW stones (which may be not NEW?) are under the captured stones?

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 Post subject: Re: Japonese counting
Post #309 Posted: Thu Sep 16, 2021 11:21 am 
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B stones are alive since a new B stone at 2-2 is clearly enabled by the capture (B cannot play that if W doesn't capture him - the played stone must be new).

And yes, generally if there is new permanent stone under any of the strings's original intersections, life cannot be questioned in any way. The tricky cases are when the new stone is elsewhere.

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 Post subject: Re: Japonese counting
Post #310 Posted: Thu Sep 16, 2021 12:55 pm 
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jann wrote:
B stones are alive since a new B stone at 2-2 is clearly enabled by the capture (B cannot play that if W doesn't capture him - the played stone must be new).

And yes, generally if there is new permanent stone under any of the strings's original intersections, life cannot be questioned in any way. The tricky cases are when the new stone is elsewhere.


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

Can we conclude that the white alone stone is dead, the four black stones are alive => 3 points of territory for black => white must continue normal play in order to get 2 points for her!

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 Post subject: Re: Japonese counting
Post #311 Posted: Thu Sep 16, 2021 5:04 pm 
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jann wrote:
kvasir wrote:
Click Here To Show Diagram Code
[go]$$B Position 1
$$ | . . . . . . .
$$ | O O . . . . .
$$ | . O . . . . .
$$ | Z O . . . . .
$$ | S X O O O . .
$$ | X X X X O . .
$$ | P X S X O . .
$$ | S O Z O X . .
$$ | O O O O X . .
$$ | . O X X X . .
$$ | O O X . . . .
$$ | X X X . . . .
$$ | . . . . . . .[/go]

I think we may declare this seki in j89 because the marked stones are dead, and the boxes are dame by j89.

I don't see why, B looks outright dead in J89 and all W inside alive thus no dame.

(Maybe you meant the closed pass-for-ko loop? But that would break most examples and we can safely assume is not allowed, the only question is why and how but that seems irrelevant here.)


Maybe I should have qualified the statement better, but Gerard was asking about the confirmation phase with its flaws, and since it was directed at me I wanted to answer with my "understanding" of the j89 semantics (but not to imply that this is really a seki in a game between two people).

Yes, I am assuming black can start taking in the double-ko when white approaches because he asked about the confirmation with its flaws, not how you could fix it.

You said that this does not match many of the examples. This is true. Examples 16-18 seem run afoul of pass-for-ko loops, yet are declared to not be seki. Then examples 19-21 show how the number of liberties do matter when there is a ko.



Click Here To Show Diagram Code
[go]$$B Example 16
$$ --------------
$$ | . O O . O . O X . X O . O X
$$ | O X X O O O O X X O O O O X
$$ | X X . X X X O X O . O X X X
$$ | . . . . X O X X X O O X
$$ | . . . . X O X . X O X X
$$ | . . . . X O X X O X X
$$ | . . . . X O O O O
$$ | . . . . . . .
$$ | . . . . . . .[/go]


The position is similar to this position which is example 16, and the white stones are declared dead without much detail.

Why is that?
* The example reasons that the seki collapses.
* One could say, like you did, that the double-ko is forbidden but then how and when is it forbidden?
* I tried to think of it as inductive process but there is the problem of allowing what is basically two moves in a row in other positions.

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 Post subject: Re: Japonese counting
Post #312 Posted: Thu Sep 16, 2021 6:27 pm 
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kvasir wrote:
One could say, like you did, that the double-ko is forbidden but then how and when is it forbidden?

Playing in the double ko itself is not forbidden OC (there are examples showing this), only the closed loop in it (which may not even exists, depending on how you read the text).

Both with Japanese rules and Chinese rules the text cannot be taken literally, you also need to look at the examples and even pro practice. For example, Chinese rules never explain how to distinguish triple ko from resisting a capture attempt in a moonshine life, but from the whole material it is clear that the first is no result on repetition while the latter is forbidden.

The intended result wrt double kos is pretty clear in J89 I think, which is why I wrote it doesn't really matter which of the possible solutions/interpretations we think is correct - at least we can be sure it is not the closed loop one.

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 Post subject: Re: Japonese counting
Post #313 Posted: Thu Sep 16, 2021 7:10 pm 
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jann wrote:
Playing in the double ko itself is not forbidden OC (there are examples showing this), only the closed loop in it (which may not even exists, depending on how you read the text).


Is this not the same as saying that at some point either player is forbidden from playing in the double ko?

Why does forbidding closed double-ko cycles always result in the correct results?

I know you are not talking about super-ko (or anything like that, at least I think I know that you don't mean super-ko :D ), and that is why I think it is completely unclear when the cycle is formed and whos burden it is to break it.

I'd say that the only thing that is clear about the j89 rules intent for closed double-ko cycles is that j89 are not the rules of the game.

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 Post subject: Re: Japonese counting
Post #314 Posted: Thu Sep 16, 2021 7:33 pm 
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kvasir wrote:
jann wrote:
Playing in the double ko itself is not forbidden OC (there are examples showing this), only the closed loop in it (which may not even exists, depending on how you read the text).
Is this not the same as saying that at some point either player is forbidden from playing in the double ko?

I don't think so. For example, the pass-once interpretation allows unrestricted (normal) play in the double ko, yet the cycle disappears by itself (and would even disappear if players were allowed to make (non-obligatory) passes for kos there later, after the first (obligatory) one).

Quote:
Why does forbidding closed double-ko cycles always result in the correct results?

I would't use such grand words, but this seems to match both all examples and common go sense. The intent is to separate kos and force playing them independently, not to create a new type of perpetual repetition that doesn't make any sense in normal go.

Quote:
I'd say that the only thing that is clear about the j89 rules intent for closed double-ko cycles is that j89 are not the rules of the game.

I'm not sure it is that bad. It has it's flaws, but still a huge step forward. It's biggest defect I seen so far is lightvector's reinforcement example - since that shows a weakness of the theory itself behind pass-for-ko, not just minor problems of the text.

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 Post subject: Re: Japonese counting
Post #315 Posted: Thu Sep 16, 2021 7:44 pm 
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jann wrote:
It's biggest defect I seen so far is lightvector's reinforcement example - since that shows a weakness of the theory itself behind pass-for-ko, not just minor problems of the text.

Even lightvector's reinforcement example is consistent within the Japanese understanding of judging L&D:
"After one side captured into a ko-shape, there is NO ko-fight following."

The position lightvector found is simply another one of those that have a one-point (= one-move) difference between the "uncapturable" and the "two-eye-formation" worlds.
I think that it were such positions with potentially "hot" ko-shapes that led to several rules disputes in Japanese professional Go. It is Japanese understanding that such ko-shapes have to be erased before the game stops.

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 Post subject: Re: Japonese counting
Post #316 Posted: Thu Sep 16, 2021 8:07 pm 
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If I were to claim that the intention of j89 was very clear in this position, the x's being dead and o's alive, would that resolve the problem or put emphasis on that j89 is very troublesome?

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



I will give my reasons in two parts, first for the black stones and then the white.

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



Now for the white stones the reason is that when black captures the white stones white is always able to reestablish stones that are alive.

Click Here To Show Diagram Code
[go]$$B :w4: pass
$$ ----------------------
$$ | O . O 5 X 2 3 O O . O
$$ | O O O X O X O O O O O
$$ | X X X O 1 O O . O . .
$$ | X . X O O O O O . . .
$$ | . X X . . . . . . . .
$$ | X X . . . . . . . . .
$$ | . . . . . . . . . . .
$$ | . . . . . . . . . . .[/go]


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


:w1: and :w3: are reestablished stones and white's original stones are therefore alive.


Note if black tries to connect the ko that white passed for it doesn't help because of the shortage of liberties.

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 Post subject: Re: Japonese counting
Post #317 Posted: Thu Sep 16, 2021 8:32 pm 
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kvasir wrote:
:w1: and :w3: are reestablished stones and white's original stones are therefore alive.

You mean :w3: only. Indeed, the enable rule may help in this particular example. The same problem was also shown in other positions though, even if not as clear-cut as this one, so the doubtfulness of pass-for-ko remains.

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 Post subject: Re: Japonese counting
Post #318 Posted: Fri Sep 17, 2021 7:25 am 
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kvasir wrote:
If I were to claim that the intention of j89 was very clear in this position, the x's being dead and o's alive, would that resolve the problem or put emphasis on that j89 is very troublesome?
Click Here To Show Diagram Code
[go]$$B
$$ ----------------------
$$ | W C W C Z . . O O . O
$$ | W W W Z W 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]


I will give my reasons in two parts, first for the black stones and then the white.

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


Now for the white stones the reason is that when black captures the white stones white is always able to reestablish stones that are alive.

Click Here To Show Diagram Code
[go]$$B :w4: pass
$$ ----------------------
$$ | O . O 5 X 2 3 O O . O
$$ | O O O X O X O O O O O
$$ | X X X O 1 O O . O . .
$$ | X . X O O O O O . . .
$$ | . X X . . . . . . . .
$$ | X X . . . . . . . . .
$$ | . . . . . . . . . . .
$$ | . . . . . . . . . . .[/go]


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


:w1: and :w3: are reestablished stones and white's original stones are therefore alive.


Note if black tries to connect the ko that white passed for it doesn't help because of the shortage of liberties.

White to play : the result for white is the following
Click Here To Show Diagram Code
[go]$$W
$$ ----------------------
$$ | W C W W C W C W W C W
$$ | W W W C 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]

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]

When comparing these to results then the marked region of the last diagram is in any case under white control.
=> when looking for white "enable NEW stones" these NEW stones should be on the complementary following area

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

with this in mind the dead stones are the following:
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]

=> seki

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 Post subject: Re: Japonese counting
Post #319 Posted: Fri Sep 17, 2021 7:59 am 
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IGS: kvasir
Gérard TAILLE wrote:
When comparing these to results then the marked region of the last diagram is in any case under white control.
=> when looking for white "enable NEW stones" these NEW stones should be on the complementary following area

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

with this in mind the dead stones are the following:


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]



Just as with double-ko that has the unfortunate pass-ko cycles we also seem to have an unfortunate side effect here, namely that new stones could be played in many positions because there is no clear rule about what counts as new alive stone. For example, if example 2 is anywhere on the board, can we now show that black can always play a new uncapturable stone at :b1: and :b3: in effected making all his stones alive everywhere?

I asked RHETORICALLY if claiming that j89 intention was very clear would resolve the issue or just demonstrate that j89 is very troublesome, because I don't think the intention was clear.

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 Post subject: Re: Japonese counting
Post #320 Posted: Fri Sep 17, 2021 8:10 am 
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Gérard TAILLE wrote:
=> when looking for white "enable NEW stones" these NEW stones should be on the complementary following area

There is no such requirement in the rules. The new stones must be related to the capture, made possible by it, that seems all. The Japanese text may be even broader slightly than Davies' "enable". Regardless of interpretation, new stone UNDER a removed stone (from the original position) certainly qualify (if the capture in question cannot be performed without this removal and re-play).


Last edited by jann on Fri Sep 17, 2021 8:18 am, edited 2 times in total.
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