On Mon, 2006-10-23 at 11:25 +0200, Erik van der Werf wrote: > On 10/23/06, Don Dailey <[EMAIL PROTECTED]> wrote: > > ... A region of 7 inside a benson > > group cannot possibly support enemy life. So moves inside > them > > by either color do not improve the position. > > Normally (under traditional Go rules) you would be right that a region > of 7 surrounded by pass-alive stones cannot be invaded successfully. > However, when using positional superko this is *not* true. The reason > is moonshine life.
I don't believe in positional superko. I know that 99.9% of the time it makes little or no difference, but I don't see how it can be correct. 2 identical configuration - each with different color to move are simply NOT the same position. However CGOS uses it - it seems to be the most popular rule and so we are stuck with it. But my solver will not use positional superko. I consider positional superko a complication of the rules and it's usually best to keep things pure and simple. Your example may illustrate a problem with superko. It's my belief that superko can create bizarre and anomalous situations like this simply because it adds complexity. Not only are repeated positions illegal, but so are repeated configurations - for no LOGICAL reason that I can think of. I think this rule is a minor wart on the wonderful Tromp/Taylor rules. PSK is bound to creates extra trouble with hash tables too. It makes some positions arbitrarily illegal. - Don > 5x5 recapture at a forbidden due to ko > > O a O # # > . O # . # > O O # # # > # # # . # > # # # # # > > This is also an illustration of why it might make sense to have pass > lift the ko ban. > > > > Right not I'm working on a perfect solver for 5x5 > > cool :-) > > Erik > _______________________________________________ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
