Japonese counting

jann · **#181**

I mentioned a similar idea some time ago (https://www.lifein19x19.com/viewtopic.php?p=259130#p259130), but I don't think captures can be ignored like this.

An anomaly or rule flaw is an unintended difference in behavior compared to some baseline. I think the first comparison should always be to continued play with normal rules. Confirmation/analysis only needs to address the removal/cleanup costs, anything else like extra ko rules are optional hacks for different problems (and source of anomalies, not surprisingly).

So in this case what would happen if play would continue? W could proceed to either accumulate 500 pts then give up the board, or make pass alive in the whole area in question. This is the baseline/reality. (see also J89 LD ex 23 commentary)

Gérard TAILLE · **#182**

Cassandra wrote:

Gérard TAILLE wrote:

Oops something goes wrong.

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

I you begin the confirmation phase by this black move that means that you try to kill white and we agree it is not possible.

If now white wants to prove she can kill black stones she will simply begin by:

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

Where is your point with this position?

It does NOT matter whether White can kill Black's stones or not during status confirmation.

The deciding question is whether you can turn White's group into a "two-eyed alive" one, even if Black moves first.
Only if you can answer this question with "yes", you have achieved "INDEPENDENT life" for White's group (probably you like this wording more).

There are TWO conditions for Black stones (which remained on the board) that shall become White's prisoners after the end of the game, i.e. without really capturing these by actual play:
:w1:

These stones did NOT achieve the property "two-eyed alive" during status confirmation.
:w2:

These stones must be fully enclosed by (nothing else than) a White group that has achieved the property "two-eyed alive" during status confirmation.

In your example, condition :w1:

is fulfilled, but condition :w2:

is not.
Therefore, the entire position is a seki.

Please note that you will not find any "dead" in my writing above. Just because this term would be only a descriptive one (and no specifying one) for Black stones that fulfill BOTH conditions :w1:

and

above.
There is NO death DURING status confirmation, which would make its way back onto the board position at the end of "play" (i.e. at the start of the status confirmation).
Whether stones are "dead" or not is decided after the status confirmation of all (relevant) groups has been finished, and derived from the combination of all these results, as I tried to explain above.

Please to not mix "two-eyed alive" with J89's or J2003's "uncapturable" / "capturable-1".

Let me try to understand through the following example you mentionned in your post https://lifein19x19.com/viewtopic.php?p=266642#p266642

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

Two questions for my understanding Cassandra:
1) Are :bt:

"two-eyed alive"
2) Are :bc:

"two-eyed alive"

Cassandra · **#183**

Gérard TAILLE wrote:

Let me try to understand through the following example you mentionned in your post https://lifein19x19.com/viewtopic.php?p=266642#p266642

In order to understand a concept you should start with asking easy questions :razz:

But nevertheless, I will explain J89 life-and-death example 4 in detail. Hopefully this will widen the understanding of the syntax.

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

Let's start with the status confirmation of Black's three stones in the corner.

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

Click Here To Show Diagram Code: [go]$$B cannot approach at "a" $$ +---------------------- $$ | . X X O . 3 . O X . . $$ | X X O O O O O O X . . $$ | a O X X X X X X X . . $$ | 4 O X , X X . . . , . $$ | X O X X . X . . . . . $$ | X O X X X X . . . . . $$ | X O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

Click Here To Show Diagram Code: [go]$$B $$ +---------------------- $$ | . X X O 5 X 6 O X . . $$ | X X O O O O O O X . . $$ | . O X X X X X X X . . $$ | O O X , X X . . . , . $$ | . O X X . X . . . . . $$ | . O X X X X . . . . . $$ | . O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

Click Here To Show Diagram Code: [go]$$B $$ +---------------------- $$ | . X X O 7 8 O O X . . $$ | X X O O O O O O X . . $$ | . O X X X X X X X . . $$ | O O X , X X . . . , . $$ | . O X X . X . . . . . $$ | . O X X X X . . . . . $$ | . O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

Click Here To Show Diagram Code: [go]$$B $$ +---------------------- $$ | . X X O 9 O O O X . . $$ | X X O O O O O O X . . $$ | . O X X X X X X X . . $$ | O O X , X X . . . , . $$ | . O X X . X . . . . . $$ | . O X X X X . . . . . $$ | . O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

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

As a matter of course, Black's group can get two eyes, if he plays first.

--------------------------

White plays first.

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

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

Click Here To Show Diagram Code: [go]$$W $$ +---------------------- $$ | . X X O O 6 . O X . . $$ | X X O O O O O O X . . $$ | . O X X X X X X X . . $$ | 7 O X , X X . . . , . $$ | X O X X . X . . . . . $$ | X O X X X X . . . . . $$ | X O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

Click Here To Show Diagram Code: [go]$$W $$ +---------------------- $$ | . X X O O X 8 O X . . $$ | X X O O O O O O X . . $$ | . O X X X X X X X . . $$ | O O X , X X . . . , . $$ | . O X X . X . . . . . $$ | . O X X X X . . . . . $$ | . O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

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

White cannot prevent this result, even if she plays first.

--------------------------

Variation:

Click Here To Show Diagram Code: [go]$$W $$ +---------------------- $$ | . X . O . X . O X . . $$ | X X O O O O O O X . . $$ | . O X X X X X X X . . $$ | 3 O X , X X . . . , . $$ | X O X X . X . . . . . $$ | X O X X X X . . . . . $$ | X O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

Click Here To Show Diagram Code: [go]$$W $$ +---------------------- $$ | . X 6 O 4 X 7 O X . . $$ | X X O O O O O O X . . $$ | . O X X X X X X X . . $$ | O O X , X X . . . , . $$ | . O X X . X . . . . . $$ | 5 O X X X X . . . . . $$ | . O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

Click Here To Show Diagram Code: [go]$$W $$ +---------------------- $$ | . X X O 8 9 O O X . . $$ | X X O O O O O O X . . $$ | . O X X X X X X X . . $$ | O O X , X X . . . , . $$ | . O X X . X . . . . . $$ | O O X X X X . . . . . $$ | . O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

Click Here To Show Diagram Code: [go]$$Bm10 $$ +---------------------- $$ | . X X O 1 O O O X . . $$ | X X O O O O O O X . . $$ | . O X X X X X X X . . $$ | O O X , X X . . . , . $$ | . O X X . X . . . . . $$ | O O X X X X . . . . . $$ | . O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

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

Variation, same result as above.

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################################

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

Second step is the status confirmation for Black's three stones at the top.

The status of Black's three stones at the left will be the same, as the position is symmetrical.

Click Here To Show Diagram Code: [go]$$B $$ +---------------------- $$ | . X X . 9 . . . X . . $$ | X X . . . . . . X . . $$ | . O X X X X X X X . . $$ | O O X , X X . . . , . $$ | . O X X . X . . . . . $$ | . O X X X X . . . . . $$ | . O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

In the sequence above that Black started, :b9:

captured White's stones at the top.

Click Here To Show Diagram Code: [go]$$Wm10 passes $$ +---------------------- $$ | . X X . X 2 4 . X . . $$ | X X . . . . . . X . . $$ | . O X X X X X X X . . $$ | O O X , X X . . . , . $$ | . O X X . X . . . . . $$ | . O X X X X . . . . . $$ | . O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

Click Here To Show Diagram Code: [go]$$Wm10 passes $$ +---------------------- $$ | . X X . B B B . X . . $$ | X X . . . . . . X . . $$ | . O X X X X X X X . . $$ | O O X C X X . . . , . $$ | . O X X C X . . . . . $$ | . O X X X X . . . . . $$ | . O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

Black's three stones got captured, but they could be re-established in total. They have two eyes.

--------------------------

White plays first.

Click Here To Show Diagram Code: [go]$$W $$ +---------------------- $$ | . X X . . X 8 . X . . $$ | X X . . . . . . X . . $$ | . O X X X X X X X . . $$ | O O X , X X . . . , . $$ | . O X X . X . . . . . $$ | . O X X X X . . . . . $$ | . O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

In the main line above, :b8:

captured White's stones at the top.

Click Here To Show Diagram Code: [go]$$Bm8 passes $$ +---------------------- $$ | . X X . 3 X X . X . . $$ | X X . . . . . . X . . $$ | . O X X X X X X X . . $$ | O O X , X X . . . , . $$ | . O X X . X . . . . . $$ | . O X X X X . . . . . $$ | . O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

Click Here To Show Diagram Code: [go]$$Bm8 passes $$ +---------------------- $$ | . X X . B B B. X . . $$ | X X . . . . . . X . . $$ | . O X X X X X X X . . $$ | O O X C X X . . . , . $$ | . O X X C X . . . . . $$ | . O X X X X . . . . . $$ | . O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

Same result as above, even if White moves first.

##########################
##########################

Your unasked question about the status of White's groups would have been answered in the posting you linked at if we ever wanted to get a result of this status confirmation for Black playing first:

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

White's stones got captured, and neither could they become re-established in total (for achieving the status "two-eyed alive"), nor partially, which would give them the chance to become turned into components of a seki in the concluding status assessment (in another environmant than here of course).

However, there remains that psychologically unfavorable "life" of the other White group, which was not currently under examination at all. Therefore. ...

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

... we are fine with letting White show what she can achieve with having the advantage of the first move.

We already know from the sequences above that White will be unable to turn her stones into a "two-eyed alive" group. No single stone of a White group under consideration will survive on the board.

--------------------------

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

The concluding result of the status confirmation has all Black groups "two-eyed alive", while all White groups are "NOT two-eyed alive".
White's "NOT two-eyed alive" stones are all completely surrounded by Black "two-eyed alive" groups; therefore, they can taken off the board after the end of the status confirmation as prisoners (being "dead").

I am very well aware that this result does not match that of J89, but as I explained in my linked posting, the authors have exaggerated here with their desire to generate a seki.
As I stated there, the White groups are completely surrounded by Black "two-eyed alive" groups EACH, and there can be NEVER EVER ANY interaction between these two seperated sections of the board.
Probably it had been this life-and-death example that caused Robert to also overextend his "local-2" in his J2003.

As a matter of course, one of both White's groups cannot be captured by actual play before the game stops.
But can any the double-ko groups in life-and-death examples 16 to 18 become captured by actual play before the game stops? NO!!! Nevertheless, these are declared "dead".

jann · **#184**

Cassandra wrote:

I am very well aware that this result does not match that of J89, but as I explained in my linked posting, the authors have exaggerated here with their desire to generate a seki.

You should look at the logic behind this. As I wrote above, the main reason for any confirmation phase is to prevent cleanup moves messing up the score. Allowing something that can not be done in actual play (or giving points for two groups where only one can be captured) is much worse than seki (which costs at most a few points on extra moves).

Quote:

As a matter of course, one of both White's groups cannot be captured by actual play before the game stops.
But can any the double-ko groups in life-and-death examples 16 to 18 become captured by actual play before the game stops? NO!!! Nevertheless, these are declared "dead".

A simple moonshine life is better for your point (not capturable by actual play still dead in all rules) - which is a different story.

Gérard TAILLE · **#185**

Cassandra wrote:

Gérard TAILLE wrote:

Let me try to understand through the following example you mentionned in your post https://lifein19x19.com/viewtopic.php?p=266642#p266642

In order to understand a concept you should start with asking easy questions :razz:

But nevertheless, I will explain J89 life-and-death example 4 in detail. Hopefully this will widen the understanding of the syntax.

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

Let's start with the status confirmation of Black's three stones in the corner.

OK Cassandra your definition is clear at least on this example.

Just a additionnal confirmation concerning your definition of "two-eyed alive" on a more difficult (but well-known) example:

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

Is it correct to say that white (with the move) can prevent black marked stone to become "two-eyed alive", according to your defintion?
If yes does that mean that black should add a move to avoid seki?

Cassandra · **#186**

jann wrote:

A simple moonshine life is better for your point (not capturable by actual play still dead in all rules) - which is a different story.

You should note that "uncapturable" is a completely different pair of shoes than "two-eyed alive".

The concept of "uncapturable" is a passive one.
It is sufficient to do NOTHING, in order to prove that a component of a seki is "uncapturable". YOUR OPPONENT must take the lead during the evidence.

The concept of "two-eyed alive" is an active one.
In many cases (expect those where a group is solidly and uncuttable connected), YOU will have to take action in order to create two taboo-points for your opponent inside your group, taking the lead during the evidence.

Cassandra · **#187**

Gérard TAILLE wrote:

Just a additionnal confirmation concerning your definition of "two-eyed alive" on a more difficult (but well-known) example:

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

Is it correct to say that white (with the move) can prevent black marked stone to become "two-eyed alive", according to your defintion?
If yes does that mean that black should add a move to avoid seki?

I suppose that this position has been developed by Robert ;-)

Especially to prove the WORDING of "after it has been captured" rules mistaken.

But it's me here, so let's ask for the deeper meaning of the condition for turning captured stones into "two-eyed alive" ones first, which was hidden beyond the surface before (supposed) Robert found this example above.
Please remember that the primary concern of such a condition were snap-back and nakade, none of which is addressed in the position above.

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

This is one possible "final" position of the status confirmation for Black's three stones at the upper edge in life-and-death example 4 of J89.

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

Let's modify it a bit.

Click Here To Show Diagram Code: [go]$$B $$ +---------------------- $$ | . X X 7 Y T T . X . O $$ | X X 5 9 . . . . X . O $$ | . O X X X X X X X . O $$ | O O X 3 X X . . . , O $$ | . O X X 1 X . O O O O $$ | O O X X X X . O . O . $$ | . O X . . . . O O O . $$ | O O X . O O O O . . . $$ | X X X . O . O . . . . $$ | . . . , O O O . . , . $$ | O O O O O . . . . . .[/go]

And let's give Black the task of creating a group with only two single eye points, in order to be sure that we apply the rule right (I know that Robert is very fond of this idea).
You will quickly notice that Black is not the very most experienced status confirmator ...

Click Here To Show Diagram Code: [go]$$Bm11 $$ +---------------------- $$ | . X X X Y T T 9 X . O $$ | X X X X 1 3 5 7 X . O $$ | . O X X X X X X X . O $$ | O O X X X X . . . , O $$ | . O X X X X . O O O O $$ | O O X X X X . O . O . $$ | . O X . . . . O O O . $$ | O O X . O O O O . . . $$ | X X X . O . O . . . . $$ | . . . , O O O . . , . $$ | O O O O O . . . . . .[/go]

Click Here To Show Diagram Code: [go]$$Bm21 $$ +---------------------- $$ | . X X X Y T 1 X X . O $$ | X X X X X X X X X . O $$ | . O X X X X X X X . O $$ | O O X X X X . . . , O $$ | . O X X X X . O O O O $$ | O O X X X X . O . O . $$ | . O X . . . . O O O . $$ | O O X . O O O O . . . $$ | X X X . O . O . . . . $$ | . . . , O O O . . , . $$ | O O O O O . . . . . .[/go]

Task completed!

Click Here To Show Diagram Code: [go]$$Bm21 $$ +---------------------- $$ | . X X X Y T Y X X . O $$ | X X X X X X X X X . O $$ | . O X X X X X X X . O $$ | O O X X X X . . . , O $$ | . O X X X X . O O O O $$ | O O X X X X . O . O . $$ | . O X . . . . O O O . $$ | O O X . O O O O . . . $$ | X X X . O . O . . . . $$ | . . . , O O O . . , . $$ | O O O O O . . . . . .[/go]

Ups! Black's captured stones are not reborn in total, so did Black create a seki for the final position of the game? Of course not!

Every single board point that was occupied by a captured Black stone must remain under the "control" of a "two-eyed alive" Black group.
I. e. NONE of these points must become part of a "two-eyed alive" White group.
If so, it is irrelevant whether such point is occupied by a Black stone or empty at the end of the status confirmation.

"Being an eye point" is equivalent to "being a reborn captured stone".

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

As you will know, this is the final position of the status confirmation for Black's marked stone at hoshi.
You will realise for sure that the board point that was occupied by Black's stone is empty. And that there is a BLACK "two-eyed alive" group around.

To keep a long story short ...

Click Here To Show Diagram Code: [go]$$W $$ +-------------------+ $$ | W W W W W W W W . | $$ | W B B B B B B B W | $$ | W B . B . B B B W | $$ | W B B B P B B B W | $$ | W B . P B P . B W | $$ | W B B B . B B B W | $$ | W B B B . B B B W | $$ | W B B B B B B B W | $$ | . W W W W W W W W | $$ +-------------------+[/go]

There is NO need for Black to add a move.

Gérard TAILLE · **#188**

Cassandra wrote:

Every single board point that was occupied by a captured Black stone must remain under the "control" of a "two-eyed alive" Black group.

I believe I understand Cassandra. The wording "control" seems fine : it is either a stone or one of the eyes of a "two-eyed alive" formation.

Now I can come back to the following position:

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

1) you can prove :bc:

are under control
2) you can prove :bt:

are under control
3) but you cannot :bc:

and

can be under control at the same time.

Eventually what will happen in the confirmation phase. Can black claim that both :bc:

and

are under control or can she only choose one group or ...?
IOW the "under control" concept is clear but it is not clear if you are allowed to add groups "under control" without precaution.

Cassandra · **#189**

Gérard TAILLE wrote:

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

1) you can prove :bc:

are under control
2) you can prove :bt:

are under control
3) but you cannot :bc:

and

can be under control at the same time.

I am always happy when I can help. Especially at the moment, when the preparatory works for the forthcoming 2021 update of our Igo Hatsuyôron 120 website have reached the "final 5 percent" (hopefully for the last time this fourth or fifth time), which are always extremely boring. A little relief is good.

##########################
##########################

The procedure is as follows.

##########################
##########################

Step :w1:

: Determine the status for each individual group

Click Here To Show Diagram Code: [go]$$B $$ +------- $$ | ? Y ? $$ | Y Y ? $$ | ? ? ?[/go]

Click Here To Show Diagram Code: [go]$$B $$ +---------------------- $$ | ? ? ? ? Y Y Y ? ? ? ? $$ | ? ? ? ? ? ? ? ? ? ? ?[/go]

Click Here To Show Diagram Code: [go]$$B $$ +---------------------- $$ | ? ? $$ | ? ? $$ | ? ? $$ | ? ? $$ | Y ? $$ | Y ? $$ | Y ? $$ | ? ?[/go]

Click Here To Show Diagram Code: [go]$$B $$ +------------------ $$ | ? ? ? ? ? ? ? Q ? $$ | ? ? Q Q Q Q Q Q ? $$ | ? ? ? ? ? ? ? ? ?[/go]

Click Here To Show Diagram Code: [go]$$B $$ +------ $$ | ? ? ? $$ | ? ? ? $$ | ? Q ? $$ | ? Q ? $$ | ? Q ? $$ | ? Q ? $$ | ? Q ? $$ | Q Q ? $$ | ? ? ?[/go]

Click Here To Show Diagram Code: [go]$$B $$ +-------------------- $$ | ? ? ? ? ? ? ? ? Y ? $$ | ? ? ? ? ? ? ? ? Y ? $$ | ? ? Y Y Y Y Y Y Y ? $$ | ? ? Y ? Y Y ? ? ? ? $$ | ? ? Y Y ? Y ? ? ? ? $$ | ? ? Y Y Y Y ? ? ? ? $$ | ? ? Y ? ? ? ? ? ? ? $$ | ? ? Y ? ? ? ? ? ? ? $$ | Y Y Y ? ? ? ? ? ? ? $$ | ? ? ? ? ? ? ? ? ? ?[/go]

There are no dependencies on other groups during the individual status determination!

##########################
##########################

Step :w2:

: Combine the results

Click Here To Show Diagram Code: [go]$$B $$ +---------------------- $$ | . B . . B B B P B . . $$ | B B P P P P P P B . . $$ | . P B B B B B B B . . $$ | . P B , B B . . . , . $$ | B P B B . B . . . . . $$ | B P B B B B . . . . . $$ | B P B . . . . . . . . $$ | P P B . . . . . . . . $$ | B B B . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

Mutual dependencies are only now to be considered, especially for determining seki (if non "two-eyed alive" groups were determined that could not be captured, or could be re-established only partially after having been captured -- but which is not the case here).

Gérard TAILLE · **#190**

Thank you Cassandra for having explained what you mean by "two-eyed alive".
It is clear to me and eventually quite easy (I mean easier that the local-2 concept of J2003

).

Now how it works with territory?

Click Here To Show Diagram Code: [go]$$B black to play $$ +------------ $$ | . . . . . | $$ | X X X X . | $$ | d O X X X | $$ | O O O O O | $$ | . . . X O | $$ +------------[/go]

In the position above the normal play for black is to play on the dame "d" and black wins the game by one point (6 against 5).
But both players pass and confirmation phase takes place.
In J2003 the result is jigo because, due to the dame, the two big groups are in seki => no territory and no prisonners.
What about your proposal? Do you take care of the dame (I mean an empty point adjacent to a white and to a black two-eyed alive group) or do you simply ignore it?
In the case this dame prevent you to recognise a territory, does that mean that white will win the game by one prisonner to zero?

Cassandra · **#191**

Gérard TAILLE wrote:

Now how it works with territory?

Click Here To Show Diagram Code: [go]$$B black to play $$ +------------ $$ | . . . . . | $$ | X X X X . | $$ | d O X X X | $$ | O O O O O | $$ | . . . X O | $$ +------------[/go]

In the position above the normal play for black is to play on the dame "d" and black wins the game by one point (6 against 5).
But both players pass and confirmation phase takes place.
In J2003 the result is jigo because, due to the dame, the two big groups are in seki => no territory and no prisonners.
What about your proposal? Do you take care of the dame (I mean an empty point adjacent to a white and to a black two-eyed alive group) or do you simply ignore it?
In the case this dame prevent you to recognise a territory, does that mean that white will win the game by one prisonner to zero?

The "駄" (= "da") in "駄目" (= "dame"; "目" is "point") means (in my understanding; likely amoung others)
-- of poor quality
-- not especially valuable
-- useless

It should be evident that the main application is with empty board points that are located between groups with two eyes (or between a group with two eyes and the fencing group of a seki, just to be complete) and where it does not matter from which side they are occupied (aka "neutral points").

Empty board points in seki are also referred to with this term. But in seki, these points should NOT be occupied by any side. Therefore, these points have another characteristic than the DAME mentioned above.
DAME in seki are equally "useless", in that they cannot / will not become territory.
But nevertheless they have a special value, in that they prevent strings from becoming captured (leaving e.g. "three points without capturing" aside here, in order to keep the text as simple as possible).

############

Now let's return to the ruleset discussion.

Under the concept of "uncapturable" (used e.g. by J89 and J2003), DAME (in seki) are absolute necessary to distinguish
-- uncapturable groups that have two eyes (and therefore surround territory) from
-- uncapturable groups that are a compound of a seki.

The need to occupy DAME outside groups with two eyes (to confirm territory inside) is a side effect of using the same term for two different kinds of board points.
If there was a specific term for "DAME in seki" in Japanese, it would be completely unnecessary to occupy "neutral points" in connection with "territory".
The remaining benefit of forcing both players to occupy ALL "neutral points" on the board would be to guarantee that NO protective move inside a group with two eyes is missed, which occupation will become mandatory due to a potential shortage of liberties (of parts of the group with two eyes that are not yet "securely" connected within that group's compound of strings).

--------------

Under the concept of "two-eyed alive", empty board points are NOT needed to distinguish
-- groups that have two eyes from
-- groups that are a compound of a seki (and as such do NOT have two eyes).

In your example, Black will win the game by one point on the board, independent of the point of "d" being unuccupied or not.

Mike Novack · **#192**

Gérard TAILLE wrote:

Thank you Cassandra for having explained what you mean by "two-eyed alive".
It is clear to me and eventually quite easy (I mean easier that the local-2 concept of J2003

).

Now how it works with territory?

Click Here To Show Diagram Code: [go]$$B black to play $$ +------------ $$ | . . . . . | $$ | X X X X . | $$ | d O X X X | $$ | O O O O O | $$ | . . . X O | $$ +------------[/go]

In J2003 the result is jigo because, due to the dame, the two big groups are in seki => no territory and no prisonners.
zero?

WHY do you say that? WHY do you think both those groups are in seki? They are both alive (in the two eye sense -- achieving two eyes cannot be prevented). The dame at "d" is irrelevant, not a point for either and filling ti does not require a response (say to maintain connectivity)

Cassandra · **#193**

Mike Novack wrote:

Gérard TAILLE wrote:

Thank you Cassandra for having explained what you mean by "two-eyed alive".
It is clear to me and eventually quite easy (I mean easier that the local-2 concept of J2003

).

Now how it works with territory?

Click Here To Show Diagram Code: [go]$$B black to play $$ +------------ $$ | . . . . . | $$ | X X X X . | $$ | d O X X X | $$ | O O O O O | $$ | . . . X O | $$ +------------[/go]

In J2003 the result is jigo because, due to the dame, the two big groups are in seki => no territory and no prisonners.
zero?

WHY do you say that? WHY do you think both those groups are in seki? They are both alive (in the two eye sense -- achieving two eyes cannot be prevented). The dame at "d" is irrelevant, not a point for either and filling ti does not require a response (say to maintain connectivity)

J89 wrote:

Article 8. Territory
Empty points surrounded by the live stones of just one player are called "eye points." Other empty points are called "dame." Stones which are alive but possess dame are said to be in "seki." Eye points surrounded by stones that are alive but not in seki are called "territory," each eye point counting as one point of territory.

J2003 wrote:

Definitions 3
…
In the final-position, a black-region / white-region is in-seki if at least one of its intersections is adjacent to a dame.
…

Gérard TAILLE · **#194**

Cassandra wrote:

Gérard TAILLE wrote:

Now how it works with territory?

Click Here To Show Diagram Code: [go]$$B black to play $$ +------------ $$ | . . . . . | $$ | X X X X . | $$ | d O X X X | $$ | O O O O O | $$ | . . . X O | $$ +------------[/go]

In the position above the normal play for black is to play on the dame "d" and black wins the game by one point (6 against 5).
But both players pass and confirmation phase takes place.
In J2003 the result is jigo because, due to the dame, the two big groups are in seki => no territory and no prisonners.
What about your proposal? Do you take care of the dame (I mean an empty point adjacent to a white and to a black two-eyed alive group) or do you simply ignore it?
In the case this dame prevent you to recognise a territory, does that mean that white will win the game by one prisonner to zero?

The "駄" (= "da") in "駄目" (= "dame"; "目" is "point") means (in my understanding; likely amoung others)
-- of poor quality
-- not especially valuable
-- useless

It should be evident that the main application is with empty board points that are located between groups with two eyes (or between a group with two eyes and the fencing group of a seki, just to be complete) and where it does not matter from which side they are occupied (aka "neutral points").

Empty board points in seki are also referred to with this term. But in seki, these points should NOT be occupied by any side. Therefore, these points have another characteristic than the DAME mentioned above.
DAME in seki are equally "useless", in that they cannot / will not become territory.
But nevertheless they have a special value, in that they prevent strings from becoming captured (leaving e.g. "three points without capturing" aside here, in order to keep the text as simple as possible).

############

Now let's return to the ruleset discussion.

Under the concept of "uncapturable" (used e.g. by J89 and J2003), DAME (in seki) are absolute necessary to distinguish
-- uncapturable groups that have two eyes (and therefore surround territory) from
-- uncapturable groups that are a compound of a seki.

The need to occupy DAME outside groups with two eyes (to confirm territory inside) is a side effect of using the same term for two different kinds of board points.
If there was a specific term for "DAME in seki" in Japanese, it would be completely unnecessary to occupy "neutral points" in connection with "territory".
The remaining benefit of forcing both players to occupy ALL "neutral points" on the board would be to guarantee that NO protective move inside a group with two eyes is missed, which occupation will become mandatory due to a potential shortage of liberties (of parts of the group with two eyes that are not yet "securely" connected within that group's compound of strings).

--------------

Under the concept of "two-eyed alive", empty board points are NOT needed to distinguish
-- groups that have two eyes from
-- groups that are a compound of a seki (and as such do NOT have two eyes).

In your example, Black will win the game by one point on the board, independent of the point of "d" being unuccupied or not.

That is clear Cassandra and quite simple which is a great advantage. The counterpart is that the results are not always the results expected by the japonese professionnals but I see another subtle drawback.

In common japonese rules the territories have a remarkable property that is never mentionned : territories are really independant to each other. As soon as a territory has been identified for say white then, even if you allow white to rearrange her territory as she want (provided it remains white territory) then the analyse of all other groups on the board does not change. OC, this gives a great consistency for all territories.

An example to understand what I mean:

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

The upper right corner is white territory according to confirmation phase

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

Even if white rearranges her territory like this then the analyse all all group in the marked area will be the same.
This is quite interesting because as soon as you have identified a territory you can safely analyse the other groups of the board by excluding any play in this territory and by assuming the corresponding stones being definitly uncapturable (even if the owner of the territory pass always).
To assure this property common japonese rules conclude often to a seki where you conclude to "two-eyed alive" and territory. That means that you lost this consistency between territories which is a pity for me.

Cassandra · **#195**

Gérard TAILLE wrote:

To assure this property common japonese rules conclude often to a seki where you conclude to "two-eyed alive" and territory. That means that you lost this consistency between territories which is a pity for me.

I am sorry, Gérard, but I really do not have any idea of what you intended to say.
If you like to re-arrange the position of the two eye-points of a group (if technically possible), please do so. Nothing outside a "two-eyed alive" group (a Black one in your example) will be affected by anything inside. And vice versa.

The only single example that I know of, where J89 has a seki, but the application of the "two-eyed alive" idea has not, is life-and-death example 4.
However, I see this as absolutely irrelevant. I hope to have made clear, why.

Contrary to a potential hidden rule for achieving the intended results of examples 16 to 18 (which lack the derivation of the intended results), I am unable to imagine which hidden rule (please remember the interdependency with example 1) should lead us to the intended result of example 4, while having absolutely no side-effects on other positions.

#############################

By the way, as far as I can remember, we have not discussed "seki" in general yet.

#############################

By the way #2, it will be impossible to avoid any differences between the intended results of J89 / J2003 and those of applying the "two-eyed alive" idea, just because the concepts of "uncapturable" and "two-eyed alive" have one very decisive diffence in their foundations. Which we haven't discussed yet, too, as far as I can remember.

Cassandra · **#196**

Gérard, concerning life-and-death example 4 ...

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

Status assessment for White's stones.

##########################

The following sequence is given in the current Japanese original of J89 as the proof for declaring White's stones alive.

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

Click Here To Show Diagram Code: [go]$$B $$ +---------------------- $$ | . X X O . 3 . O X . . $$ | X X O O O O O O X . . $$ | . O X X X X X X X . . $$ | 4 O X , . . . . . , . $$ | X O X . . . . . . . . $$ | X O X . . . . . . . . $$ | X O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

Click Here To Show Diagram Code: [go]$$B $$ +---------------------- $$ | . X X O 7 X 5 O X . . $$ | X X O O O O O O X . . $$ | . O X X X X X X X . . $$ | O O X , . . . . . , . $$ | . O X . . . . . . . . $$ | 6 O X . . . . . . . . $$ | . O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

Would you agree that their own rules were not really understood?

Gérard TAILLE · **#197**

Cassandra wrote:

Gérard TAILLE wrote:

To assure this property common japonese rules conclude often to a seki where you conclude to "two-eyed alive" and territory. That means that you lost this consistency between territories which is a pity for me.

I am sorry, Gérard, but I really do not have any idea of what you intended to say.
If you like to re-arrange the position of the two eye-points of a group (if technically possible), please do so. Nothing outside a "two-eyed alive" group (a Black one in your example) will be affected by anything inside. And vice versa.

The only single example that I know of, where J89 has a seki, but the application of the "two-eyed alive" idea has not, is life-and-death example 4.
However, I see this as absolutely irrelevant. I hope to have made clear, why.

Contrary to a potential hidden rule for achieving the intended results of examples 16 to 18 (which lack the derivation of the intended results), I am unable to imagine which hidden rule (please remember the interdependency with example 1) should lead us to the intended result of example 4, while having absolutely no side-effects on other positions.

#############################

By the way, as far as I can remember, we have not discussed "seki" in general yet.

OK Cassandra let's take an example you know very well:

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

You prove yourself that white is able to prove her white marked group is "two-eyed alive" (see https://lifein19x19.com/viewtopic.php?p=266583#p266583)

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

If I understand correctly your proposal that means that the four marked points above are territory for white and white gains 7 points in this part of the board.
If it is territory I expect this territory is completly independant of the rest of the board even if I rearrange this territory for example:

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

Now you can see that, if you analyse the board with this arrangement, all white stones on the board becomes "two-eyed alive" where no black stone group is "two-eyed alive" => all the board is white territory.

OC you can say that I am not allowed to proceed like this and I can agree with you because it is not the point. I only say it is a pity to lose this remarkable property of territories which exists in all (?) the current territory rules. Nothing else, simply a pity Cassandra.

Gérard TAILLE · **#198**

Cassandra wrote:

Gérard, concerning life-and-death example 4 ...

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

Status assessment for White's stones.

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The following sequence is given in the current Japanese original of J89 as the proof for declaring White's stones alive.

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

Click Here To Show Diagram Code: [go]$$B $$ +---------------------- $$ | . X X O . 3 . O X . . $$ | X X O O O O O O X . . $$ | . O X X X X X X X . . $$ | 4 O X , . . . . . , . $$ | X O X . . . . . . . . $$ | X O X . . . . . . . . $$ | X O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

Click Here To Show Diagram Code: [go]$$B $$ +---------------------- $$ | . X X O 7 X 5 O X . . $$ | X X O O O O O O X . . $$ | . O X X X X X X X . . $$ | O O X , . . . . . , . $$ | . O X . . . . . . . . $$ | 6 O X . . . . . . . . $$ | . O X . . . . . . . . $$ | O O X . . . . . . . . $$ | X X X . . . . . . . . $$ | . . . , . . . . . , . $$ | . . . . . . . . . . .[/go]

Would you agree that their own rules were not really understood?

Yes Cassandra I will never disagree with you the fact that J89 is unclear and difficult to understand ;-)

J2003 is far better indeed.

Cassandra · **#199**

Gérard TAILLE wrote:

Yes Cassandra I will never disagree with you the fact that J89 is unclear and difficult to understand ;-)

J2003 is far better indeed.

I am very sure that you know that this was NOT the question.

It is not surprising that it will run into problems, if you use a J89 life-and-death example for the judgement of other rulesets that is dramatically flawed in itself.

Cassandra · **#200**

Gérard TAILLE wrote:

OC you can say that I am not allowed to proceed like this and I can agree with you because it is not the point. I only say it is a pity to lose this remarkable property of territories which exists in all (?) the current territory rules. Nothing else, simply a pity Cassandra.

Oh, I am fine with the fact that a feature that might help simplifying the status assessment in the "uncapturable" world, does not exist under "two-eyed alive", if applied without thinking.

You must not mix both worlds together. There is a very decisive fundamental difference, which we haven't revealed yet.

It you ever wanted to use this feature in the "two-eyed alive" world, you are forbidden to rearrange the eye space of a "two-eyed alive" group that has DAME.
Simple solution, isn't it

Japonese counting

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