|Table of contents||Table of diagrams
White is independently alive
No capture without ko
White is dead
White is dead again
AdamMarquis: Since it is a beginner exercise, should this case not also be pointed out? Black's descent to the edge after White takes the throw-in makes it so that White can't approach. The result is seki (with a sending-two-returning-one option for White).
What if black takes though? Won't black have killed white without ko? -Ned G.
Brent: Well, in that case it would simply be a ko that Black didn't fight. (= If Black captures , then yes, Black wins the ko and kills White. But in compensation White gets to move twice somewhere else on the board -- once after and once after Black captures with . See ko fights for a more detailed explanation.
Bill: Don't be confused by the diagram. Black cannot take ( below) without taking the ko.
White just doesn't have the liberties needed anymore. (See next variant for at .) This is 21 points for Black in gote. This seems big enough for either player not wanting to wait . . . but should wait, it's a big ko threat.