terminology - broken ladder/ladder works

[xed_over]

When do you say a ladder works, or the ladder is broken.
Are we speaking for the one being chased? Or the one doing the chasing? Or can it be either one?

So if my stones are trapped inside a ladder, then the ladder is broken, right? Or did the ladder work for my opponent who captured the stones? Did the ladder both work (for my opponent), and was broken (for my captured stones) at the same time?

I get the sense that both usages are used, and inconsistently, depending the context and which side we're talking about.

For example, in Lee Sedol's famous broken ladder game (2003 KAT cup), Lee chased a ladder that lived. So technically, the ladder was not broken, right? The ladder worked? Why do we call it a "broken ladder"? It worked for white, but did not work for black (Lee).

[Shenoute]

I've always understood "the ladder is broken" as meaning that the ladder did not work anymore, i. e. that the stones that could previously be captured in a ladder can no longer be.

[yoyoma]

It's always from the point of view that the attacker can kill the stone.

Ladder works = I can kill this stone because the ladder works.
Ladder is broken = I cannot kill this stone because the ladder is broken.

[Bill Spight]

The way I learned it, a ladder is a technique for capturing a stone or stones. A ladder breaker is a stone played so that the ladder technique no longer works, so that the stone or stones are not captured; IOW, the ladder is broken. Also, a ladder breaker may be a stone already on the board, so that a contemplated ladder would not work.

[xed_over]

ok, all that makes sense.

I just keep getting it turned around in my head.

[Uberdude]

I agree with the others about being from the attackers side. As a side point if there are some stone(s) which currently can't escape from a ladder, and then the person in the ladder plays a stone which means the ladder no longer works we call it a ladder breaker (and the laddering player faces a choice of answering and then the stones escaping from the ladder, or ignoring to fix the ladder and facing some local loss, or in some cases answering in a way which maintains the ladder working). However I have also come across people (and maybe even books?) that also use "ladder breaker" to refer to a stone played by the person who wants to capture some stones in a ladder in the future which, if answered locally in the normal way (like some peep or shoulder hit), means the ladder would now work. However I don't like to call those breakers and instead call them "ladder makers" which sounds similar and makes more sense to me as they make the ladder work. I don't know how widespread that term is, but I don't recall it confusing anyone.

[DrStraw]

Al these comments make me think that a ladder is not really the best way to capture stones unless there is no other choice. A lot of beginners learn the technique and automatically play to capture using a ladder. Later they are surprised to find that it doesn't work because a ladder breaker was played.

The first technique to look for should be a net and only if there is none should the ladder be contemplated.

[Shenoute]

The first technique to look for should be a net and only if there is none should the ladder be contemplated.

This is the conclusion of the first chapter of Lessons in the Fundamentals :
1) can I catch it in a net?
2) can I catch it in a ladder?

It is not that rare on Tygem to have 5d opponents play a ladder when a net (albeit a slightly convoluted one) would have done the job.

[Uberdude]

Al these comments make me think that a ladder is not really the best way to capture stones unless there is no other choice. A lot of beginners learn the technique and automatically play to capture using a ladder. Later they are surprised to find that it doesn't work because a ladder breaker was played.

The first technique to look for should be a net and only if there is none should the ladder be contemplated.

Nets aren't always better than ladders: for example nets leave peeps (which could be ladder breakers/makers for another ladder), ko threats, or due to the netted stone still being on the board with liberties some scope for shortage of liberties tesujis (such as Shuei's famous escape from a net). The shape from capturing a stone or stones in a ladder is usually thicker and with less bad aji than a net. On the other hand a net often only requires one move to capture the stone, whereas a ladder requires two once a breaker is played. But in some situations the net doesn't gain a tempo so for those cases I would actually say a ladder is usually better than a net. For example in this (not so mainline: normally white should atari at 11 before connecting at 10 which means black can trade the corner for the top side, but perhaps the whole board position means white doesn't like that direction) joseki both the net and ladder are gote for white (in fact with the ladder you could omit the honte capture and take sente) but the ladder is better due to the thicker resulting shape (this of course assumes white has the ladder (a.k.a the ladder works for white) so has the choice).

$$B
$$ --------------------+
$$ . . . . . . . . . . |
$$ . . . . 9 . . . . . |
$$ . . . 3 8 7 5 4 . . |
$$ , . . . 0 2 6 1 . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |

Click Here To Show Diagram Code

[go]$$B
$$ --------------------+
$$ . . . . . . . . . . |
$$ . . . . 9 . . . . . |
$$ . . . 3 8 7 5 4 . . |
$$ , . . . 0 2 6 1 . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |[/go]

$$Bm11 Ladder
$$ --------------------+
$$ . . . . . . . . . . |
$$ . . . 2 X 3 . 5 . . |
$$ . . 4 . O X X O . . |
$$ , . . 6 O O O X . . |
$$ . . . . . . . 1 . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |

Click Here To Show Diagram Code

[go]$$Bm11 Ladder
$$ --------------------+
$$ . . . . . . . . . . |
$$ . . . 2 X 3 . 5 . . |
$$ . . 4 . O X X O . . |
$$ , . . 6 O O O X . . |
$$ . . . . . . . 1 . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |[/go]

$$Bm11 Net
$$ --------------------+
$$ . . . . . . . . . . |
$$ . . 4 2 X 3 . 5 . . |
$$ . . . X O X X O . . |
$$ , . 6 . O O O X . . |
$$ . . . . . . . 1 . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |

Click Here To Show Diagram Code

[go]$$Bm11 Net
$$ --------------------+
$$ . . . . . . . . . . |
$$ . . 4 2 X 3 . 5 . . |
$$ . . . X O X X O . . |
$$ , . 6 . O O O X . . |
$$ . . . . . . . 1 . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |[/go]

So a better rule of thumb would be:
-If a stone can be trapped (not captured, it's still on the board) in a net or captured and removed from the board in a ladder in the same number of moves then a ladder is better.
-If a stone can be trapped in a net or trapped in a ladder from which it cannot currently escape in the same number of moves then a net is better.

The first technique to look for should be a net and only if there is none should the ladder be contemplated.

This is the conclusion of the first chapter of Lessons in the Fundamentals :
1) can I catch it in a net?
2) can I catch it in a ladder?

Isn't there another part of that book though where he advocates playing the atari (which leads to a netty squeeze) not direct net on the cutting stone after the standard 3-3 invasion sequence of a 4-4 plus large knight's move? Or another where there is a choice of nets and he advocates playing one starting with an atari, being more forceful and better shape to take liberties.

[Pio2001]

In some french books, it is said "The ladder is good for White", or "The ladder is good for Black". This way, no problem.

[John Fairbairn]

(which leads to a netty squeeze)

I have to assume the north of England is a foreign country to you, otherwise you have a rather vivid imagination!

[ez4u]

In some french books, it is said "The ladder is good for White", or "The ladder is good for Black". This way, no problem.

In many (most?) Japanese books as well.

[Shenoute]

Isn't there another part of that book though where he advocates playing the atari (which leads to a netty squeeze) not direct net on the cutting stone after the standard 3-3 invasion sequence of a 4-4 plus large knight's move? Or another where there is a choice of nets and he advocates playing one starting with an atari, being more forceful and better shape to take liberties.

Yes, in the following position for instance, he advocates playing like this instead of netting immediately at 'a'.

$$B
$$ --------------------+
$$ . . . . . . . . . . |
$$ . . . . . X O . . . |
$$ . O . X . X O . O . |
$$ , . . . 2 O X O . . |
$$ . O . 3 a 1 X . . . |
$$ . . . . . . . . O . |
$$ . . . . . . . . . . |

Click Here To Show Diagram Code

[go]$$B
$$ --------------------+
$$ . . . . . . . . . . |
$$ . . . . . X O . . . |
$$ . O . X . X O . O . |
$$ , . . . 2 O X O . . |
$$ . O . 3 a 1 X . . . |
$$ . . . . . . . . O . |
$$ . . . . . . . . . . |[/go]

[Black 'a'] captures white just as surely, but when there are two ways to capture with one move, the firmer way is correct. It's worth reflecting upon the value of the firmness of BlacK 1 (...)

[Uberdude]

Shenoute, yeah that's the example I was thinking of. Interesting that after white escapes he has 3 rather than 2 liberties though. If white does pull out at 2 so that black plays 3 I agree it's better for black than the other net as 3 puts more pressure on the white one space jump to the right. But what if white doesn't do that but exchanges 3 for 2? That 3 could be somewhat helpful in the future but then there are no more forcing moves. With the other net 3 would also be sente and depending how black replies white can get some other forcing moves. With both of the nets white's push on the right is sente, though I suppose with the first net if black answers by solidly connecting on the left that has some nice effect to weaken white's one point jump.

John, I spent many childhood holidays in Yorkshire, but as I had to look up netty either that wasn't far enough north or my conversations with the locals didn't cover such topics. Our cottage there did have a former netty out the back though!

[Shenoute]

@ Uberdude

Yes, I have the same questions. Apparently, Kageyama holds this position

$$B
$$ --------------------+
$$ . . . . . . . . . . |
$$ . . . . . X O . . . |
$$ . O . X . X O . O . |
$$ , . . . . O X O . . |
$$ . O . 2 3 1 X . . . |
$$ . . . . . . . . O . |
$$ . . . . . . . . . . |

Click Here To Show Diagram Code

[go]$$B
$$ --------------------+
$$ . . . . . . . . . . |
$$ . . . . . X O . . . |
$$ . O . X . X O . O . |
$$ , . . . . O X O . . |
$$ . O . 2 3 1 X . . . |
$$ . . . . . . . . O . |
$$ . . . . . . . . . . |[/go]

as better than this one

$$W
$$ --------------------+
$$ . . . . . . . . . . |
$$ . . . . . X O . . . |
$$ . O . X . X O . O . |
$$ , . . . . O X O . . |
$$ . O . . X 2 X . . . |
$$ . . . . . 1 . . O . |
$$ . . . . . . . . . . |

Click Here To Show Diagram Code

[go]$$W
$$ --------------------+
$$ . . . . . . . . . . |
$$ . . . . . X O . . . |
$$ . O . X . X O . O . |
$$ , . . . . O X O . . |
$$ . O . . X 2 X . . . |
$$ . . . . . 1 . . O . |
$$ . . . . . . . . . . |[/go]

Maybe because this peep would help w more than the one he could get on the upper side?...