Weak Carpenter's Square
The weak carpenter's square is a carpenter's square without the connection at the corner of the shape. The vital point is the same, but this time White kills the corner by playing at a.
That is, without the black stone at , changes the status of the group from "White kills by ko" to "White kills unconditionally".
If Black plays first, then playing at a lives. Black lives with a even if is occupied by a white stone.
After a and b are miai: a White play at a creates a squared four, while a White play at b forces black to connect at c which reduces his eyespace to a bulky five.
Table of contents | Table of diagrams Weak carpenter's square White can kill White can kill White can kill variation Endgame technique not really a carpenter's square not really a carpenter's square |
Discussion
There are many ways for white to kill after . This is just one variation
After
,
at
is an auto atari so Black has no other option than to let white connect at
.
If Black has secured life by playing on the vital point, there is an important endgame technique for White to remember: the forcing moves at 1 and 3.