The volcano is sleeping temporarily, isn't it ?


I'll try to define later. Perhaps it will become clearer what I mean further down here in my posting.


But life of this single stone does not follow from application of "user-friendly".

So I'll have to study "capturable-2" for a deeper understanding of your concept and to try to find a way how we can come together.


In the meantime let's have a look on this mysterious stone in the 1989 Nihon Kiin rules that cannot be captured after some other stones of the same colour have been captured.

First of all, it is important to know that there is no plural in Japanese. Whether 石 is "stones" or "stone" can be made accessible by the context of the text only. So it may be somewhat difficult to grasp what is really meant, especially in a rule text (which securely could be written more well-defined in Japanese, too).

In my amateurish opinion (I'm not the expert for Japanese) the original Japanese text could also be interpreted as

Stones that have become reborn (that is have got a successor of the same colour on its primary board points) and cannot be captured (any more) after they had been captured (earlier), are called living stones.

But you are right when you say that the above sentence does not give the application within the 1989 Nihon Kiin rules examples.

The original comment to the respective rule clause shows positions of Snap-Back only. But Snap-Back is not a problem at all. For example, ...

Click Here To Show Diagram Code

[go]$$ before Snap-Back
$$ |--------------
$$ |X X O . O . O
$$ |X . O O O O O
$$ |X W X . . . .
$$ |O X X X X . .
$$ |O O O O X . .
$$ |. O . O X . .
$$ |O O O O X . .
$$ |. . . . . . .[/go]

Click Here To Show Diagram Code

[go]$$ after Snap-Back
$$ |--------------
$$ |. . O . O . O
$$ |. X O O O O O
$$ |O W X . . . .
$$ |O X X X X . .
$$ |O O O O X . .
$$ |. O . O X . .
$$ |O O O O X . .
$$ |. . . . . . .[/go]

... there is a White stone on the same marked board point in both diagrams.

Nakade stones inside a "dead" opponent's group provide no difficulties at all, too.

Click Here To Show Diagram Code

[go]$$ before capture
$$ |------------
$$ |W W . X O .
$$ |X X X X O .
$$ |O O O O O .
$$ |. O . O O .
$$ |O O O O O .
$$ |. . . . . .[/go]

Click Here To Show Diagram Code

[go]$$ after capture
$$ |------------
$$ |W C . . O .
$$ |. . . . O .
$$ |O O O O O .
$$ |. O . O O .
$$ |O O O O O .
$$ |. . . . . .[/go]

The marked board points are occupied (or could be occupied) by White's stones in both diagrams. Generally speaking, a White stone may be succeeded by an eye-point, too.


The real problems arise at least in examples #1, #4, and #5.

Click Here To Show Diagram Code

[go]$$ example #1
$$ |-------------------
$$ |. X X O . . . . . .
$$ |W X X O . . . . . .
$$ |X O O O . . . . . .
$$ |X X X . . . . . . .
$$ |. . . . . . . . . .[/go]

The difference between "at least one" and "all of" for Black's group has been shown in my "status for the Nihon Kiin examples" posting. It may become a minor or even insignificant one when realizing what happens with White's groups in #1, #4, and #5.

Click Here To Show Diagram Code

[go]$$ end of status sequence for White
$$ |-------------------
$$ |X P P O . . . . . .
$$ |B X . O . . . . . .
$$ |X O O O . . . . . .
$$ |X X X . . . . . . .
$$ |. . . . . . . . . .[/go]

White's primary stone has got a Black successor.
The "new" crossed White stones are successors of two of Black's stones.

Click Here To Show Diagram Code

[go]$$ example #4
$$ |-------------------
$$ |. X . . X X X O X .
$$ |X X O O O O O O X .
$$ |. O X X X X X X X .
$$ |. O X . . . . . . .
$$ |X O X . . . . . . .
$$ |X O X . . . . . . .
$$ |X O X . . . . . . .
$$ |O O X . . . . . . .
$$ |X X X . . . . . . .
$$ |. . . . . . . . . .[/go]

Let's look for the Nihon Kiin status of White's upper side group.

Click Here To Show Diagram Code

[go]$$ end of status sequence for White
$$ |-------------------
$$ |. 9 X . X X X C X .
$$ |9 9 C C C C C C X .
$$ |. O 9 X X X X X X .
$$ |P O X . . . . . . .
$$ |. O X . . . . . . .
$$ |P O X . . . . . . .
$$ |. O X . . . . . . .
$$ |O O X . . . . . . .
$$ |X X X . . . . . . .
$$ |. . . . . . . . . .[/go]

One of White's "new" stones on the left is a successor of one of Black's stones. The other one is successor of an empty board point.
None of the stones of White's chain in evaluation has got a successor.
What is very important in my opinion: White's captured stones and her "new" ones are situated within two areas of the board that are separated by independently alive groups from each other.

Click Here To Show Diagram Code

[go]$$ example #5
$$ |-------------------
$$ |. O X X . O X . . .
$$ |X X O X . O X . . .
$$ |X X O X X O X . . .
$$ |O O O O O X X . . .
$$ |. . . . . . . . . .[/go]

Evaluation sequence for White's single stone in the corner is as for example #1, so the result will be the same (this stone itself has no successor). The status of White's 3-stone chain on the right remains.

Click Here To Show Diagram Code

[go]$$ end of status sequence for White
$$ |-------------------
$$ |. O 9 9 X C X . . .
$$ |. . O 9 X C X . . .
$$ |W W O 9 9 C X . . .
$$ |O O O O O 9 X . . .
$$ |. . . . . . . . . .[/go]

Two of White's "new" stones on the left are successors of two of Black's stones.
None of the stones of White's group in evaluation has got a successor.
Again, both areas of the board ("captured" vs. "new") are separated by the independently alive Black group in the middle. This equals the "#4-effect".


If we take the results of #1, #4, and #5 together (1989 Nihon Kiin rules claim that all of White's groups are "alive") we can get an idea of what deeper concept is applied within the examples for White's chains. I would give this concept the name "borrowing life" (the term "conditional life" would mix up with the usage for potential life in Ko-situations during "Play"):


If and only if

• the capture of White's chain of stones under evaluation by Black enables White (= she can "force" it)
• to occupy at least one board point with a "permanent" stone (= it cannot be captured thereafter)
• that otherwise (= Black does not insist on capturing White's chain) remains occupied by one of Black's stones or empty

White's chain is called "borrowing alive".


It will be no surprise that I do not like this concept at all.

_________________
The really most difficult Go problem ever: https://igohatsuyoron120.de/index.htm
Igo Hatsuyōron #120 (really solved by KataGo)

Do not confuse "user-friendly reading of a particular ruleset" with "user-friendly rules"! The Simple Rules are user-friendly rules. J1989 are not. Only their reading can be made a bit user-friendly.

Not a single stone lives for itself. "independently alive" is a per-string property though.

I have been aware of the missing plural in Japanese. This implies a duty to provide context where necessary. Like expressing singular as "one stone".

(Will read the rest of your message later.)

The corner group is not independently alive, is it?

Compare this also to the following:

Click Here To Show Diagram Code

[go]$$
$$ ---------------
$$ | . X O . O X .
$$ | X . O . O X .
$$ | O O O O X X .
$$ | X X X X X . .
$$ | . . . . . . .[/go]

_________________
A good system naturally covers all corner cases without further effort.

Black's corner 3-stone chain in #4 can be forced into a 2-eye-formation, so it is "independently alive".

Both of Black's corner chains in #2 cannot.

_________________
The really most difficult Go problem ever: https://igohatsuyoron120.de/index.htm
Igo Hatsuyōron #120 (really solved by KataGo)

"user-friedly" in the subscript of the diagrams refers to the "... reading" rules in your primary posting.

_________________
The really most difficult Go problem ever: https://igohatsuyoron120.de/index.htm
Igo Hatsuyōron #120 (really solved by KataGo)

In #2, it is a white chain that is of interest.

_________________
A good system naturally covers all corner cases without further effort.

Click Here To Show Diagram Code

[go]$$
$$ ---------------
$$ | . X O . O X .
$$ | X . O 1 O X .
$$ | O O O O X X .
$$ | X X X X X . .
$$ | . . . . . . .[/go]

After Black 1, the first move of the evaluation of the status(es) of White's chain(s), none of White's chains can be forced into a 2-eye-formation.

_________________
The really most difficult Go problem ever: https://igohatsuyoron120.de/index.htm
Igo Hatsuyōron #120 (really solved by KataGo)

Unlike you, I am not worried about new stones occurring beyond partition lines by independently alive stones. It is similar to an exchange due to a ko fight. Japanese rules should not be viewed as having only one kind of locality but rather they have a hierarchy of locality from global via ko exchange environment, local-2, independently alive group region, two-eye-formation to living string.

There is also the process from unsettled to settled (with or without long cycles). Often it is unsettled shapes that let us wonder a lot what exactly "local" should be.

Not "Local is beautiful" but "Terminal is easy" should be the maxime.

What you look for as a common feature of #1 to #5 is capturable-2. But I said so before.

Yeah, capturable-2 seems to make the difference. When combined with a non-stone-like treatment of a chain.

Please find attached a table, in which I tried to compare your J2003 (as far as I understood it) with my idea, applied on several classes of generalised positions.

There are only two classes with a deverging result (in respect to what will become independently alive / "2-eyed" respectively "dead").
Both have in common capturable-2 and a heterogeneous treatment of what had been a chain.

That's what I suspected before, concerning 1989 Nihon Kiin rules, and referred to as "not being consistent".

During "Play", a chain of stones behaves like a single stone. It is treated as a unit. The unit has liberties, the unit can be taken of the board only in toto.

Why suddenly (after crossing the bridge between "Play" and "Evaluate") allowing the board-points that had been occupied by such a unit not to be handled in common ?
Why suddenly claiming one of two statuses, possessed by one fraction of the units primary points, for the entire unit ?

EDIT:
Corrected "Comparison.pdf"

_________________
The really most difficult Go problem ever: https://igohatsuyoron120.de/index.htm
Igo Hatsuyōron #120 (really solved by KataGo)

No. The different stones of a string do NOT have different statuses. Under J2003, the available life and death statuses (before an in-seki classification) in a final-position are:

black uncapturable string
black capturable-1 string
black capturable-2 string
black dead string
white uncapturable string
white capturable-1 string
white capturable-2 string
white dead string

That each hypothetical-sequence of the analysis of a particular string does various things (like establishing a permanent-stone on one intersection of the analysed string's intersections) does not change that.

If you really wanted strict consistency, then you would need stone scoring: Only the intersection colour determines its score contribution.

Your attached table:

Classes? What would be the classification?

I have not checked every detail of yout table, but #1 under J2003 you have analysed wrongly. It has one capturable-1 and one capturable-2 string and each string's status applies to ALL its stones.

Sorry Robert,

A typo. Of course Black's chain in example #1 is capturable-1. Has been corrected.

I'm well aware of the fact that the status given is given uniform for either a single stone or a chain (i.e. "all of its stones") after the end of the evaluation.

But the status found may be found only for one single stone of the complete chain (i.e. "at least one of its primary points").

I think we can use 3 questions to highlight the subtle, but decisive, distinctions between our approaches.

• Should chains be treated as a whole (i.e. "for all") ?
• Should status determination of a chain depend on previous results for others ?
• Should "local" be bordered by "living" chains of each colour ?

I suppose your answers being "NoYesNo", mine are "YesNoYes".

_________________
The really most difficult Go problem ever: https://igohatsuyoron120.de/index.htm
Igo Hatsuyōron #120 (really solved by KataGo)

Firstly I specify for which purposes I design a ruleset. Then I try to design the ruleset for those purposes. Your questions are of comparatively little relevance for that.

Here the major purpose is to design a Japanese style ruleset. Such requires certain characteristica for life, as stated earlier.

If I were to design some territory scoring ruleset with some form of life concept in it, then I would follow a much greater freedom (much greater than yours).

As stated earlier, you have chosen the long and hard way when starting with "life".

I had the understanding of your first posting that your aim is the creation of a user-friendly reading of the 1989 Nihon Kiin rule set.

I also had the understanding that you want to use "independently alive" only during Analysis.

Should this be true, you would have to explain, which of the examples on Life & Death you have chosen that must not fulfill your requirements (or elsewhere would make some precedence necessary to fit its Nihon Kiin result).

_________________
The really most difficult Go problem ever: https://igohatsuyoron120.de/index.htm
Igo Hatsuyōron #120 (really solved by KataGo)

Regarding the first question, are you saying that of a connected string of stones, some may have a different status than the others?

_________________
A good system naturally covers all corner cases without further effort.

No, as I have written in my reply to Robert's posting, it is beyond dispute that a (= one and only one) status is given to a chain (= connected string of stones), what means to all of its elements (= stones). This is not the moment when "as a whole" vs. "at least one" will provide a problem.

The problem - in my opinion it is one - arises before, during the course of the evaluation / determination sequence, in the event of the chain in evaluation being captured.

The fate of a single stone that has been captured during Analysis is bound to the fate of its successor. What - im my opinion - must be true with a chain, too. Remember that during "Play" stone and chain are treated in the same manner, they have equal characteristics.

A successor of a chain must mandatory occopy all of its primary points. If any of its primary points is occupied by an opponent's stone, there will be no successor of the chain.

But among chains that can be captured, 1989 Nihon Kiin rules and also Robert's capturable-1 give "life" to

• one permanent stone "under the stone" (= Uttegaeshi)
• one permanent chain "under the chain" (= Nakade)
• one permanent stone "under the chain" (= e.g. Black's 4-stone chain in example #1)

In my judgement, the latter is inconsistent.

Black's 4-stone group in #1 in theory could consist of - let's assume - more than 280 stones (may be even more, I don't know) on the whole board. Of which only one (= 1 !) will have a successor.

Instead of assuming "live" to the whole Black chain (and also to the single White stone that will have no successor at all - that's due to "would enable" respectively "local-2"), resulting in "Seki" for #1, I would like it more to have "removable" for the single White stone and "stable" (can neither be forced to 2-eyed nor to removal as a whole) for Black's group, resulting in "Seki" for #1, too. "not independently alive" for both would give the same result.

_________________
The really most difficult Go problem ever: https://igohatsuyoron120.de/index.htm
Igo Hatsuyōron #120 (really solved by KataGo)

The inconsistency of the kind you describe can occur. The consistency between WAGC-alive and J2003-alive is always given though, and I consider it to be much more relevant.

I am not sure why you ask about "to use 'independently alive' only during Analysis". For Scoring, 'independently alive' is applied. This is used for strategic planning before Analysis. So why do you suggest I might use it only during Analysis?

For 'independently alive' as in the Simplified Japanese Rules, I do not care (much) which rare examples might behave differently.

For J2003, I did care a lot which examples would behave how:
- In principle, ALL examples from Japanese professional or related sources should fit: rules examples, games, books, journals.
- As an exception, when Japanese professionals changed their judgement over time, then their most recent judgement should fit. (Like 3-points-without-capturing shape or moonshine life.)
- As an exception, where the rules experts among the Japanese professionals provided purely artifical examples AND were inconsistent / incomplete in their analysis, not necessarily all their judgements must fit. (I.e., J1989 official commentary examples II.16-18.)
- Where purely artifical examples were invented by Western rules experts, any somewhat reasonable judgement should be considered fitting.

J2003 Rules meet these requirements. (And do so better and much more exhaustively than what the Japanese professionals had studied as examples.) Slightly different rulesets, which have not been worked out so far though, might have chances as well. (Winfried Borchardt had an idea to compile something like J2003 but with a 2-layer process of life types. I think he has not finished working out that yet.)

Do you refer to the 1979 rules text ?


During the stage of Analysis, "independently alive" is the one and only status, your user-friendly rules look for.


I suppose you even care less what the reasoning might be (e.g. within "user-friendly").


I feel very uncomfortable with your statement above.

Sentence 1 (which in itself provides no problem, because it only says "use state-of-the-art") follows "Example provided by Japanese." >>> "Example evaluated be Japanese."

Sentence 2 follows "Example provided by Japanese." >>> "Characteristics of the example judged by N.N. (probably non-Japanese)." >>> "Characteristics of the Japanese evaluation judged by N.N. (probably non-Japanese)" >>> "Japanese judgement judged by non-Japanese."

Sentence 3 follows "Example provided by non-Japanese." >>> "Characteristics of judgement judged by non-Japanese." >>> "Non-Japanese judgement judged by non-Japanese."

_________________
The really most difficult Go problem ever: https://igohatsuyoron120.de/index.htm
Igo Hatsuyōron #120 (really solved by KataGo)

WAGC-alive: I refer to http://home.snafu.de/jasiek/wagcmod.html

Within my rulesets, I care very much what the reasoning is.

Concerning your uncomfortable feeling about sentences 2 + 3, why are you uncomfortable with them? Because it is well known that the Japanese professionals changed the rulings of 3-points-without-capturing shape or moonshine life over time?! Don't you believe that? Then read, e.g., the rules texts J1949, WAGC, J1989! - And what is your problem with my characterization of Examples 16-18? That I have been able to describe the huge gaps in their analysis, to find move-sequences overlooked by the professionals, to point out their inconsistency in their analysis and to assess the missing relation between terms in commentary to terms in the rules?

@ Harleqin: A supplement to my posting above.


Let's further refer to example #1 and assume that the "desired" final result is "Seki" (i.e. none of the 5 stones will be taken off the board as prisoners).

Following the precondition that only "not alive" (used as in 1989 Nihon Kiin rules) chains within opposing "alive" chains will become "dead" (i.e. will be taken off the board as prisoners), we can consider 2 alternatives, both giving the chains identical statuses.

1) Both White's single stone and Black's 4-stone chain are "not alive".
2) Both White's single stone and Black's 4-stone chain are "alive".

In alternative 1) none of the 2 chains in evaluation is situated within opposing "alive" stones, so both of them will remain on the board.
In alternative 2) there is nothing "not alive" that probably could be taken off the board.


Reasoning could be as follows:

1) "not alive"
White's single stone will be captured and its primary point will not constitute part of an "alive" chain.
White's stone is in danger (because"not alive") to be turned into a prisoner, should Black's chain become "alive". But:
Black's 4-stone chain will be captured and its primary points (i.e. "all of") will not constitute part of an "alive" chain".
So Black's chain is "not alive", too.

2) "alive"
Black's 4-stone chain will be captured and one of its primary points (i.e. "at least one") will constitute part of an "alive" chain.
White's stone is in danger (because now being inside opposing "alive" chains") to be turned into a prisoner. So it is mandatory that its status must become "alive", too.
White's single stone will be captured and its primary point will not constitute part of an "alive" chain. It becomes obvious now that the procedure used to get Black's chain to "life" will not work here.
A second procedure is wanted in desperation. Suddenly it is regognized that during the evaluation sequence White had occupied at least one point of the board, where NO White stone had been before in the primary position. Let's turn this into the second procedure, using "would enable ...".
Be aware that there could be examples, where "where no White stone had been before" could go too far away from the battlefield (i.e. beyond "living" groups).


I hope it has become apparent that the reasoning for 1) is simpler than that for 2), needs only one procedure instead of two, and provides no side-effects on chains not evaluated so far - in contrary to 2).

If there remains some uncertainty, it might be preferable to chose "not alive", because this is the choice that has NO side effect on neighbouring chains, never.


If you go through the results of "my idea" for the 1989 Nihon Kiin rules examples, you will recognize that in the somewhat "mysterious" examples (containing Double- or Triple-Ko) it will make no difference to the final result (excluding their well-defined parts, as Bent-Four), whether the chains have been evaluated as "stable" or "removable". Really important is that they did NOT get the status "2-eyed". What is true also with Roberts "independently alive" vs. "not independently alive", using "user-friedly".

This way - using the minimal possible scope for (independent) life - minimises potential side-effects in situations one had not been aware of before.

_________________
The really most difficult Go problem ever: https://igohatsuyoron120.de/index.htm
Igo Hatsuyōron #120 (really solved by KataGo)