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Re: Question regarding last play

Posted: Fri May 31, 2013 12:46 pm
by oren
Jocke wrote:
oren wrote:Are you suggesting black pass force white to pass? That could be bad if a point was missed by black. I've had that happen... so white should be able to take it.
But white didn't take it the first time. So white has already wasted hir chance.
Ok, so you're suggesting a rule that when black passes after white, white is forced to pass. I guess the only issue to me is that it's really not needed for any purpose. White will pass and end the game. (until Bill Spight comes and finds some odd endgame scenario :) )

I thought you were suggesting white plays, black passes, and white is forced to pass which wouldn't make any sense.

Re: Question regarding last play

Posted: Fri May 31, 2013 12:53 pm
by Jocke
oren wrote:
Jocke wrote:
oren wrote:Are you suggesting black pass force white to pass? That could be bad if a point was missed by black. I've had that happen... so white should be able to take it.
But white didn't take it the first time. So white has already wasted hir chance.
Ok, so you're suggesting a rule that when black passes after white, white is forced to pass. I guess the only issue to me is that it's really not needed for any purpose. White will pass and end the game. (until Bill Spight comes and finds some odd endgame scenario :) )

I thought you were suggesting white plays, black passes, and white is forced to pass which wouldn't make any sense.
Hehe, when I think about it, it doesn't make any sense to force white to pass but it doesn't make any sense to let white play on the board either. :bow:

Or? :study:

Re: Question regarding last play

Posted: Sat Jun 08, 2013 10:51 pm
by Mef
oren wrote:
Jocke wrote:
oren wrote:Are you suggesting black pass force white to pass? That could be bad if a point was missed by black. I've had that happen... so white should be able to take it.
But white didn't take it the first time. So white has already wasted hir chance.
Ok, so you're suggesting a rule that when black passes after white, white is forced to pass. I guess the only issue to me is that it's really not needed for any purpose. White will pass and end the game. (until Bill Spight comes and finds some odd endgame scenario :) )

I thought you were suggesting white plays, black passes, and white is forced to pass which wouldn't make any sense.
The first oddity that comes to mind is white passing after black wins a ko fight. Black does not need to fill the ko because his pass will end the game, and all stones on the board at the end of the game are alive. In theory this could lead to a situation where black has more ko threats than white has legal moves, so a one eye+ ko shape group lives.

Re: Question regarding last play

Posted: Sun Jun 09, 2013 11:42 am
by Bill Spight
oren wrote:Are you suggesting black pass force white to pass? That could be bad if a point was missed by black. I've had that happen... so white should be able to take it.
Jocke wrote: But white didn't take it the first time. So white has already wasted hir chance.
oren wrote: Ok, so you're suggesting a rule that when black passes after white, white is forced to pass. I guess the only issue to me is that it's really not needed for any purpose. White will pass and end the game. (until Bill Spight comes and finds some odd endgame scenario :) )

I thought you were suggesting white plays, black passes, and white is forced to pass which wouldn't make any sense.
Mef wrote: The first oddity that comes to mind is white passing after black wins a ko fight. Black does not need to fill the ko because his pass will end the game, and all stones on the board at the end of the game are alive. In theory this could lead to a situation where black has more ko threats than white has legal moves, so a one eye+ ko shape group lives.
The Ing 4 pass procedure prevents this. It is a bit complicated, but if you are going to end play by consecutive passes instead of by agreement, then, IMO, it is the best procedure currently in use, except for the difficulty in distinguishing between fighting ko and disturbing ko.

Traditionally, games ended by agreement, but the reason why was forgotten and that caused a problem when Takahashi did not agree to end a game vs. Segoe. See http://senseis.xmp.net/?TenThousandYearKo%2FRulesCrisis

To avoid the kind of Moonshine Life position that Mef suggests at the end of the game, the game cannot simply end with two consecutive passes. Ending play by agreement worked for centuries, and I think it can still work. What you need is to provide for the game to end without agreement if only one player wants play to end. (Under tournament rules, you also want to provide for play to end even if neither player wants to.)

One possibility is to say that if Player A passes in Position P and suggests ending the game, then if Player B passes the game ends. If Player B does not pass, then if play returns to Position P, the game ends. (Under these rules a pass lifts a ko or superko ban. So in a Moonshine Life kind of position say that Player A takes the ko, Player B passes, Player A passes and suggests ending the game, and then Player B takes the ko.)

See also http://senseis.xmp.net/?MoonshineLife , http://senseis.xmp.net/?SpightRulesII , and http://senseis.xmp.net/?SpightJapaneseStyleRules (Article 9).