# Gokyo Shumyo, Section 1, Problem 13 / Solution

Main line: Hashimoto Utaro 9p
Variations: Dieter, unkx80, Bill Spight, tderz, xela

White lives

Main line

If Black tries to save his monkey jump marked stone. White throws in at and creates shortage of liberties at a with . If Black resolves the shortage of liberties with , White plays , making miai of b and c.

We shall gradually investigate the alternatives back to .

Variation 1

Depending on the situation on the upper side, Black can choose not to resolve the shortage of liberties, but instead play here.

Variation 1 (cont)

captures four stones, and throws in again at .

Variation 1 (cont)

White connects, and gets one eye, and if Black makes the other one false with , White runs away with .[2] If Black is strong in the environment of , however, he can kill White, so one has to bear in mind that the status of the white group heavily depends on the upper side conditions. (this variant is elaborated in [3] )

Variation 2

This is the variation in which Black permits his monkey jump to be cut off by playing ; it results in seki. is important. The rest of the moves are more or less forced. and complete the shape.

White has all of her stones in one chain, so in order to capture them, Black has to play either a or b. In both cases a live bent four shape results. So Black will play neither of them, giving seki.

Variation 2 (mistake at 3)

(10 recaptures at 8)

in the above diagram is important for the shape created. If White carelessly plays descent at , Black kills at .

Variation 3

If Black answers as here with , White doesn't make a fool of herself and she lives with and . Playing at , instead, would enable Black to make seki.

[1] White can start with another move too, but it is worse in terms of points:

Variation 4

If at , at reverts to Variation 2. If at , at reverts to Variation 1.
Of course, Black prefers this way of allowing White life.

Variation 4a

If at , then White plays at a and lives by seki.

Wrong (10 at 7)

The points and are both vital points in this position and if White rushes to take one, Black takes the other. Here, throwing in as before with doesn't work any more.

Wrong (ii)

, , and it's all over.

[2]

There is an unwritten convention in life-and-death problems that to escape is to live.

[3]

Gokyo Shumyo, Section 1, Problem 13 / Solution last edited by Dieter on July 31, 2014 - 09:26