Shortage of Liberties

As a first example, Black would like to play a here to make two eyes, but his string of stones would then be in atari, his only liberty being Therefore after Black plays at a White can capture his whole string by playing at .

If the White stone , for example, were not there as in this diagram, Black can play ( a in the previous diagram) and now Black is not in atari, Black has two liberties ( and ) and Black can therefore not be captured. If White plays later at , Black is in atari but can capture at , creating two eyes and he is therefore alive (But be aware, this is only the case as long as the other Black stones don't get captured)

In both situations, the eyeshape is the same, but the shortage of liberties changes the status.

Therefore, don't take away your own liberties without good reason.

Shortage of liberties and damezumari

The phrase shortage of liberties is the standard translation in English literature for damezumari. Because the English liberty has a different range of meanings than the Japanese dame, the phrase can easily be (mis)used for any situation where there is a low number of liberties. Usually, ...

• When a stone has only one liberty, it is said to be in atari.
• In a race to capture, the losing side does not have enough liberties, but because that is a given, it is not put in those terms.

So, there must be a certain objective which superficially, shapewise, normally would be possible but in this particular case is not, due to the shortage of liberties. Even then, not all situations where one is short of liberties for a certain objective, would be called damezumari.

More nuances at Shortage of liberties / Discussion

More examples

Here, White would normally be able to play atari at a but due to the special properties of the corner, in particular the fact that the corner point has only two neighbors, he cannot play a and must play an approach move at b first.

This is called connect and die or external liberty shortage by Robert Jasiek. It can occur, e.g, in connection or endgame tactics.

The bamboo joint may be short of liberties.

Black would like to split White's groups but cannot, due to shortage of liberties.

This oshi-tsubushi relies on a suicide. Other instances rely on self-atari or a missing possibility to escape from atari.

Applications

Shortage of liberties is the source of many basic tactics.

• snapback
• oiotoshi (this is very common)
• crane's nest tesuji (which is just a special case of oiotoshi)
• shunt
• Ladder
• seki
• approach move
• inability to play oshitsubushi
• damezumari examples
• double shortage of liberties
• double snapback