|Table of contents||Table of diagrams
2 and 3 are miai (i)
2 and 3 are miai (ii)
2 and 3 are miai (ii continued)
White kills at 'a'
White kills at 'b'
White ignores threat of 'a'
White ignores threat at 'b'
Variation (2 at 1-2 point)
After , which makes an eye at the circled point, a and b are miai for life.
If White captures a Black stone with , makes a second eye. Howver, if Black doesn't respond, White a kills the group.
at the other 1-2 point is wrong. With , Black is dead. Even if Black is allowed two moves in a row, he can't live.
When Black plays here, White can choose between a and b to kill Black. Someone with an opinion which is the better ?
We must look at the ko threats black has. Here black can make two eyes by playing both 'a' and 'b', so either of them can be used as a ko threat. However, this is the only threat black can have from this position.
Here black will again live by having both 'a' and 'b', so they are both ko threats. Again, no more threats for black. So, are the moves equal?
Let's say the ko was crucial enough that white had to ignore this threat. Can white have ko threats of her own to kill black again, if another big ko appears in the game? is the best she can do, threatening to make a ko for black's life at 'a'.
Here, however, white can make a threat to kill the black group without a ko (by filling at ). 'a' is still playable, for the ko would be a hanami ko for white. Therefore, I feel that 'b' was slightly better than 'a', but the difference is really small. --Dansc
What is this diagram about? It isn't part of the immediately prior sequence. -- SGBailey
Connecting with Black , as shown here, is also wrong. and leave a and b as miai for the kill.
Making the eye as large as possible, with here, seems live, but it is not the solution from the book. After , follows, and Black lives as shown.
Alternatively, if would be followed by , White a, .
is answered by .
If Black 1 is a mistake, then it must be because White can next play at 2. If Black now plays 3, White 4 kills the entire black group. But ...
The authors of the variations shown here, have not yet found the reason why in the Main Line of *Solution* is preferred to of *Analysis by Members of Sensei's Library*.
I received the following suggestion. White 2 is sente against Black 1. If Black doesn't answer ...
4 at 1. The result is ko.
Bill: Maybe this is the main line.
To avoid that, maybe White should start with . Now fills and is sente. This is better for White than the next diagram.
In the Main Line solution , White's descent at is not sente.