Life In 19x19

Fedya wrote:This showed up in Tsumego Pro today, and it's not quite the normal problem, but one that I found interesting if difficult. No kos or sekis here:

$$Bc Black to, well, you figure it out
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O O O . . O , . . . . . , . . . |
$$ | . . . X X O O X . O . . . . . . . . . |
$$ | . . . . X X O . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------

Click Here To Show Diagram Code

[go]$$Bc Black to, well, you figure it out
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O O O . . O , . . . . . , . . . |
$$ | . . . X X O O X . O . . . . . . . . . |
$$ | . . . . X X O . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

[Expletive Deleted]. These things always come so quickly to the rest of you!

Fedya wrote:[Expletive Deleted]. These things always come so quickly to the rest of you!

It didn't come quickly to me. I remember learning this when I was 4 kyu.

Dfan:

Fedya wrote:E2, I presume?

Don't presume. Read it out. THAT is how to get to 5k.

Fedya wrote: Is there a good way to figure out which move -- the direct connection vs. the tiger mouth -- is better in that situation? Similar shapes show up all the time in my games, and probably a lot of other players' games, too. Kageyama has something in this connecting vs. cutting chapter of Lesons in the Fundamentals of Go. Davies translates, "If you thoughtlessly choose the wrong way, your connection may even turn out to be bad", but Kageyama doesn't tell us how to figure out the right way.

Well, he just says it depends on the stones to the left, but that's a bit too vague to help.

Is there a good way to figure out whether a solid connection, a hanging connection, or a keima connection is best? (It sounds like you never heard of a keima connection. I hadn't either, at your level. ) It goes without saying that some reading or seeing is involved. And there is a fourth option: no connection at all. The first tesuji book I bought, a small pamphlet by the Nihon Kiin when I was 4 kyu, spent the very first examples on the question of which kind of connection to make. It was enlightening, and gave me a pretty good sense of when to play which. But, OC, there is no magic bullet.

I remember having the question for protecting a single stone on the second line when I was a beginner. A lot of beginners descend to the first line. Good in spirit, but usually bad in practice, because your opponent can simply descend to the first line and make another threat. I knew enough to avoid that, as a rule. The question I had was whether to make a solid connection or a hanging connection. It was over 25 years before I learned the answer. And not the complete answer, OC. There are almost always exceptions in go.

Back in '98 and in the next few years I had the opportunity to analyze some games with Jujo Jiang and Rui Naiwei. One thing that struck me about Rui was how often she pushes the limits of the possible. When you are learning I think that it is good to emulate that. Instead of protecting against imaginary threats by your opponent, ask yourself what can I get away with. That is why some beginners descend to the first line to save a single stone. They think that that gives them more territory. Once they realize that that is not generally the case, they stop making that play. It is, as a rule, too thin. Going for what you can get away with means that your opponent may be able to take advantage of your thinness. If so, you can learn from that. But if you underreach, you may just wonder why you lost the game.

Fedya wrote:Is there a good way to figure out which move -- the direct connection vs. the tiger mouth -- is better in that situation?

Some useful rules to thnk about:

1. Do I need to preserve eye shape because my group is not already secure? If so think about the hanging connection first.

2. Is my group big enough or strong enough to not need eyes? Then play the solid connection so as to avoid giving the opponent ko threats.

3. Is my group close to the corner with a possible hane for the opening on the other boundary? Then look for a better protection such as a keima or ogeima which will protect the other side as well.

Fedya wrote:This showed up in Tsumego Pro today, and it's not quite the normal problem, but one that I found interesting if difficult. No kos or sekis here:

$$Bc Black to, well, you figure it out
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O O O . . O , . . . . . , . . . |
$$ | . . . X X O O X . O . . . . . . . . . |
$$ | . . . . X X O . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------

Click Here To Show Diagram Code

[go]$$Bc Black to, well, you figure it out
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O O O . . O , . . . . . , . . . |
$$ | . . . X X O O X . O . . . . . . . . . |
$$ | . . . . X X O . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

DrStraw says that the answer is the first thing to look at. Well, it is the first thing that he looks at, and it is the first thing that I look at. But we are experienced players. The first thing inexperienced players look at is, I think, the hane. The first lesson from this problem, which comes from a middle game joseki, is why the hane does not work. And I think that that is the most important lesson. As DrStraw points out, the move that works in this position will not always work. But then the hane will not work, either. That's why I think that don't play the hane is the more important lesson here.

dfan wrote:

This is called "the double knight's move tesuji" (at least by me ) because of the relationship of your stone with both of the stones it is connecting. It is hard to deduce using first principles but you should learn to look for the pattern.

Here's another example, from everybody's favorite book, Get Strong at Tesuji:

$$Bc Black to play and connect
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . O O O . . . . .
$$ | . O X X O O X . .
$$ | . X . . . . X . .
$$ | . . X . . . . . .
$$ | . . . . . . . . .
$$ -------------------

Click Here To Show Diagram Code

[go]$$Bc Black to play and connect
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . O O O . . . . .
$$ | . O X X O O X . .
$$ | . X . . . . X . .
$$ | . . X . . . . . .
$$ | . . . . . . . . .
$$ -------------------[/go]

Is that read out well enough?

Fedya wrote:

dfan wrote:

This is called "the double knight's move tesuji" (at least by me ) because of the relationship of your stone with both of the stones it is connecting. It is hard to deduce using first principles but you should learn to look for the pattern.

Here's another example, from everybody's favorite book, Get Strong at Tesuji:

$$Bc Black to play and connect
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . O O O . . . . .
$$ | . O X X O O X . .
$$ | . X . . . . X . .
$$ | . . X . . . . . .
$$ | . . . . . . . . .
$$ -------------------

Click Here To Show Diagram Code

[go]$$Bc Black to play and connect
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . O O O . . . . .
$$ | . O X X O O X . .
$$ | . X . . . . X . .
$$ | . . X . . . . . .
$$ | . . . . . . . . .
$$ -------------------[/go]

$$Bc Black to play and connect
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . O O O . . . . .
$$ | . O X X O O X . .
$$ | . X . 3 2 . X . .
$$ | . . X . 1 . . . .
$$ | . . . . . . . . .
$$ -------------------

Click Here To Show Diagram Code

[go]$$Bc Black to play and connect
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . O O O . . . . .
$$ | . O X X O O X . .
$$ | . X . 3 2 . X . .
$$ | . . X . 1 . . . .
$$ | . . . . . . . . .
$$ -------------------[/go]

$$Bc Black to play and connect
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . O O O . . . . .
$$ | . O X X O O X . .
$$ | . X 3 2 4 . X . .
$$ | . . X 5 1 . . . .
$$ | . . . . . . . . .
$$ -------------------

Click Here To Show Diagram Code

[go]$$Bc Black to play and connect
$$ | . . . . . . . . .
$$ | . . . . . . . . .
$$ | . O O O . . . . .
$$ | . O X X O O X . .
$$ | . X 3 2 4 . X . .
$$ | . . X 5 1 . . . .
$$ | . . . . . . . . .
$$ -------------------[/go]

Is that read out well enough?

Not quite.

Am I still missing something?