Double shortage of liberties

  Difficulty: Beginner   Keywords: Tactics, Go term

Chinese: 金鸡独立 (jin1 ji1 du2 li4)
Japanese: 両オス手なし (ryou osu te nashi)
Korean: 양자충 (兩自充, yang-ja-chung)

Double shortage of liberties, which is also called two-sided approach block by Robert Jasiek, usually refers to the loss of a capturing race because one side requires approach moves on either side of a group.

This is a conventional example from Gokyo Shumyo, Section 1, Problem 38 / Solution. Observe that although both the black+circle and white+circle groups appears to have two liberties each, Black is unable to make approach moves at a or b without putting himself in self-atari. Hence, White has effectively captured the black+circle stones.

Large-scale double shortage of liberties  

In this example (from TFG9 Black Upper Left) White wins the race despite some apparently bad shape. Black will never be able to play safely at a, now. And the white+circle stones must be captured by Black before he can approach from the other direction.

See also:

Double shortage of liberties last edited by hnishy on May 30, 2018 - 03:13
RecentChanges · StartingPoints · About
Edit page ·Search · Related · Page info · Latest diff
[Welcome to Sensei's Library!]
Search position
Page history
Latest page diff
Partner sites:
Go Teaching Ladder
Login / Prefs
Sensei's Library