Net versus ladder

Keywords: Tactics

In general, capturing a stone in a net is considered better than capturing it in a ladder, because a net does not run the risk of a ladder block on the other side of the board.

There are exceptions to this rule, mostly when the extra liberty that a net gives is detrimental, in which case a ladder is quicker (the opponent is in atari until the end).

Table of contents
Example

Example of exception

See also
Table of diagrams
White cuts
Net 1
kiki points
Net 2
kiki points
Ladder
Taisha variation
Net continuation
Common mistake

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Example

When white cuts at , black can capture this stone in three ways: a ladder or two ways of net.

and net the White stone, because White's attempt to escape fails as shown in the diagram. White should play elsewhere (tenuki) instead of .

If White plays one of the circled points, Black must defend to prevent the escape. (such points are called kiki in Japanese). In addition, White's play on one of the squared points prevents Black's net - he must capture by the ladder.

is another net (sometimes called "jaw strap"). Again, White's attempt to escape fails.

This net gives White more kiki points on the upper side and fewer on the left side.

The net is better, because the ladder allows white to play a ladder block somewhere along the path of the ladder.

Tapir: Even if there is no ladder breaker played by White, Black needs to capture at a time just in case. That is what I took from Kageyama: to capture with a ladder you need two moves, to capture with a net only one.

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Example of exception

The ladder is better than the net in some exceptional cases. This is a variation of the taisha joseki. What the books say is that is only playable when the ladder is good for White. In this case, capturing the stone at a is sente, threatening b.

If this net continuation were good, White could play at instead of in the above diagram independent of the ladder, thereby avoiding the most difficult variations.

After these plays, however, Black has a good result, and the possibility of a black peep at d remains. Also forces . Both of these effects are there because the marked black stone is still on the board.

For comparison, see the above ladder diagram. White's capture at a forces Black to defend at b.

Note that the often seen mistake here is needless sente move before : this loses sente and is an example of ignoring the 123 principle. (However: checking with Lizzie shows that LZ prefers that mistake.)

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