[Welcome to Sensei's Library!]

StartingPoints
ReferenceSection
About


Aliases (info)
Ladders
Shicho

Paths
Tesuji
34PointHighApproa...
44PointLowApproac...

Referenced by
LibertyIntroductory
Tsumego
LadderBreaker
CuttingPoint
SqueezeTesuji
AtariAtari
Cut
GoBooks
AboutInfluence
DrivingTesuji
CuttingStones
UnderstandingWiki...
TrumpetConnection
BadAji
NetExample7
LooseLadder
TaishaJoseki
KnightSMoveCap
YiSeTol
EssentialGoTerms

Homepages
CraigDaniel
KarlKnechtel

 

Ladder
Path: Tesuji   · Prev: DoubleSnapback   · Next: Net
  Difficulty: Beginner   Keywords: Tesuji, Go term

A ladder (Japanese term: シチョウ shicho,Chinese 征zheng ) is a technique for capturing stones. At each step the attacker reduces the defender's liberties from two to one.

Example

[Diagram]
Ladder

Black B1 starts a ladder to capture the WC stone.


[Diagram]
Playing out the ladder

If White tries to escape, Black can at each time play atari and White will be captured.

Clearly White should see this and not play W2.



[Diagram]
A long ladder

Ladders may span a large part of the board. If for example Black captures the white stone in a ladder with B1, the ladder will go all over the board if White tries to escape, resulting in the next diagram.


[Diagram]
A long ladder

If White tries to escape, the ladder will continue in this way. Of course, as it stands, this is a disaster for White.

But if there had been a white stone at a, White could now capture a stone and would stand to capture more because of all the double ataris that White can play. Such a stone which stops a ladder from working is called a ladder-breaker.



[Diagram]
Ladder-breaker points

A simple technique for reading a ladder is to see six diagonal lines from the start of the shicho.[1] Unfortunately SL does not permit me to draw lines, so I have to make do with marking all the points instead. Except for a, b and c, any black stone (only) on the marked points will make a ladder-breaker.

However, if there are both black and white stones on the marked points, please read the ladder 'manually': visualise it on the board. That's not so hard, either.


[Diagram]
Not a ladder-breaker

Why is a black stone at a in the previous diagram (the marked stone here) not a ladder-breaker?


[Diagram]
Not a ladder-breaker

This diagram shows why - on the second line, White can play at W5 instead of d in the diagram, rendering the BC stone useless.

The reader might want to figure out why having a black stone at b or c in that diagram doesn't make a ladder-breaker.

Besides, note that the ladder-breaker points I have marked don't include the points on the first line. Go and figure which of these points make ladder-breakers, and which do not.

--unkx80



[1] Dieter: Kageyama says: No shortcuts. Read the ladder. Always. See Practicing Reading Out Ladders.


See also:



Path: Tesuji   · Prev: DoubleSnapback   · Next: Net
This is a copy of the living page "Ladder" at Sensei's Library.
(OC) 2003 the Authors, published under the OpenContent License V1.0.