Pio2001 wrote:How can it be ? I was under the impression that under japanese rules, if the only thing left on the board is an unfinished ko, the intersection that is inside is not a point of territory (because of the unwritten rule that says that if we lift ko bans and give the sente to the opponent, the ko may be recaptured, therefore one of the stones around the empty intersection is dead).
Why is it different in this game ? According to the same reasoning, the white stone A16 should be dead, therefore the intersection A15 is dame, therefore White has no territory in A13 until she fills A15.
In the hypothetical play, after Black's ko capture, White can afford to make a pass to recapture the ko and eventually capture the whole Black group. Korean rule does not mandate a pass for the ko capture, but there is no problem doing so. Thus, in both rules, the whole Black group is captured at the end of the hypothetical play. (Technically, Black fails to create a new stone uncapturable for White.)
There are a few possible Black strategies, but none is successful. If you still have trouble following the hypothetical play, I will give you a few diagrams.
