# Hanezeki / Discussion

Sub-page of Hanezeki

unkx80: The following was the old contents on why hanezeki is a seki. Unfortunately, I found the presentation confusing, and so I decided to rewrite it.

# Seki with strings in atari; Explanation why White cannot capture the stones

Hane seki - explanation

tderz: captures three stones, but also costs a liberty.
In semeais you prefer to start from the outside, resp. taking away the liberties from the other group.
However the left inside the black group form a local seki, hence White is unable to start there.
Thus White puts herself at a disadvantage to start anywhere else than the preferred place (outside/other liberties).
This disadvantage continues after , as White cannot approach from the outside by a, as it would be suicide and create a life-enabling shape for Black.
White is forced to fill another (own) inside liberty -> b.

Hane seki - explanation

tderz: Now, after Black , White is down to atari c,
but so is Black and thus has to remove the 3 white before playing .

Hane seki - explanation

tderz: After , White needs to play in order to be able to kill,
however Black is able to play atari and be 1 liberty ahead .

Herman Hiddema: More important is what happens if white does not play in the above diagram!

Hane seki - explanation

pass, pass

Herman Hiddema: Black continues by filling a liberty at , then capturing at . See the next diagram...

Hane seki - explanation

Herman Hiddema: White has no option but to play , to keep the black group dead. This doesn't help however, as black now plays , putting the white group in atari.

The above diagrams are the true reason that neither player should capture in the original diagram. At the start, both players have a big eye. By capturing you remove your own big eye. See also BigEyeSmallEye

Hane seki - wrong starting position

tderz: The position started as here and White had to find a way to survive (play h).

blubb: Why doesn't White play at the marked point? [1]

[1] Blubb is right, my starting diagram is worthless, it must be different.:

Hane seki - verification

tderz: Replying to blubb's question Why not to capture at
After ,

• White has sente and 4 liberties (1 outside + 2 inside + 1 shared inside liberty = 4 in total),
• Black only has 4 liberties (1 shared liberty + 3 inside liberties (5 for the yon-nakade are reduced to 3 as Black is forced to created sanmoku nakade by a necessary capturing move in gote) = 4 in total)
Hane seki - variation

tderz: After black becomes necessary, as is .
Black loses by 1 liberty (2 : 3).

Hanezeki / Discussion last edited by Unkx80 on March 5, 2008 - 14:10