Life In 19x19

Hello, I went to this page on SL : Clamp and I saw this diagram :

Click Here To Show Diagram Code

[go]$$ B Black 1 is a Clamp
$$ . . . . . . . . . |
$$ . . . . . O . . . |
$$ . . . . . . . . . |
$$ . . . . . O . . . |
$$ . . . X . a . . . |
$$ . . . . X W 1 . . |
$$ . . . . . b . . . |
$$ ----------------[/go]

with this comment :

As can be seen in the example, the [second line clamp] is a common [end-game tesuji]. It makes ''a'' and ''b'' [miai].

I wonder what happend for black if white choose 'b' for

Click Here To Show Diagram Code

[go]$$B
$$ . . . . . . . . . |
$$ . . . . . O . . . |
$$ . . . . . . . . . |
$$ . . . . . O a . . |
$$ . . . X 5 3 4 b . |
$$ . . . . X W 1 6 . |
$$ . . . . . 2 . . . |
$$ ----------------[/go]

what would black do after ? tried at a or b but can't find any good continuation for black...
or is that something wrong in my sequence ?

Any help welcome

a and then atari stone above to capture in ladder. If you don't have the ladder you can still fight and break white's shape. Usually it's good for black. Also 5 can make ko instead of connect if you don't like white keeping the points with this tesuji (black does get stronger on the outside in sente but it's a bit ugly):

Click Here To Show Diagram Code

[go]$$B
$$ . . . . . . . . . |
$$ . . . . . O . . . |
$$ . . . . . 9 0 . . |
$$ . . . . . O 7 . . |
$$ . . . X 5 3 4 8 . |
$$ . . . . X W 1 6 . |
$$ . . . . . 2 . . . |
$$ ----------------[/go]

Thanks Uberdude, I like the idea of the ladder.

oca wrote:Hello, I went to this page on SL : Clamp and I saw this diagram :

$$ B Black 1 is a Clamp
$$ . . . . . . . . . |
$$ . . . . . O . . . |
$$ . . . . . . . . . |
$$ . . . . . O . . . |
$$ . . . X . a . . . |
$$ . . . . X W 1 . . |
$$ . . . . . b . . . |
$$ ----------------

Click Here To Show Diagram Code

[go]$$ B Black 1 is a Clamp
$$ . . . . . . . . . |
$$ . . . . . O . . . |
$$ . . . . . . . . . |
$$ . . . . . O . . . |
$$ . . . X . a . . . |
$$ . . . . X W 1 . . |
$$ . . . . . b . . . |
$$ ----------------[/go]

with this comment :

As can be seen in the example, the [second line clamp] is a common [end-game tesuji]. It makes ''a'' and ''b'' [miai].

I wonder what happend for black if white choose 'b' for

You need to be careful about examples on SL. Remember, it is written by amateurs. I checked the page history and found out that this example arose from a question by a kyu player who asked if was a clamp. So it is.

But I would be very surprised if this diagram appeared in more than a handful of pro games, if any. Why? Because Black is too weak outside of the corner.

Click Here To Show Diagram Code

[go]$$ B Black 1 is a Clamp
$$ . . . . . . . . . . |
$$ . . . . . . O . . . |
$$ . . . . X . . . . . |
$$ X . . . . . O . . . |
$$ . . . . B . a . . . |
$$ . . . . . B W 1 . . |
$$ . . . . . . b . . . |
$$ ----------------[/go]

This is a much more likely position for the clamp. First, Black is strong enough outside not to worry about the safety of the stones, no matter how White answers the clamp. Second, Black has a stronger reply if White captures .

Not that you can't learn something by playing around with such examples. But you are much better off studying examples from pro games or books. Then you can trust that the play in the example is actually a good idea. (Unless the point is that it is a mistake, OC.) There are such examples on the SL page.

There are times when a player will make a second line clamp in the corner, even though he is weak outside. Here is an example.

Click Here To Show Diagram Code

[go]$$Wcm83 Yamamoto Genkichi (W) - Hayashi Tetsugen, 1803
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . X O O . . O . . . |
$$ | . . . X . . . . O . X O . O . . O . . |
$$ | . . X , X . . . . , X X O X X X O . . |
$$ | . . O . . . . . . . O O O X O X X X . |
$$ | . . . X O . . . . . . . X O O O O X . |
$$ | . . O O . . . . . . X X . . O X O O . |
$$ | . . . . . . . . . . . . X X O X . X . |
$$ | . . X . X . . . . . . . . O X . X . . |
$$ | . . . 2 . . . . . , . . . O X , . X . |
$$ | . . 1 . . . . . . . . . . O X . . X . |
$$ | . . . . . . . . . . . O X O X . X O . |
$$ | . . . . . . . . . . . . O X . . X O . |
$$ | . . . 9 . . . . . . . . O . X X O . . |
$$ | . 5 . . . . . . . . . . . O X O O . . |
$$ | . 3 4 X . . . . . , . . . . O , . . . |
$$ | . 6 8 . . X . O . . . . . . . O . . . |
$$ | . 7 . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

The clamp, , is played as a probe to leave aji in the corner. (OC, it threatens to live there if Black does not reply.) It is a good exercise to consider what the aji is if descends instead of connecting.

Bill, thanks for the detailed response.

Bill Spight wrote: ...
You need to be careful about examples on SL
...
Not that you can't learn something by playing around with such examples.
...

Ok thanks, good to know...

Bill Spight wrote: You are much better off studying examples from pro games or books

I do that too... I'm currently reading "So you want to play go, level 2" for 19 to 10 kyu and also "Fundamental Principles of Go, written by Yilun Yang" which is a bit harder for me... I feel that I understand what the book says, but when I do the exercices, I full wrong...

Bill Spight wrote: It is a good exercise to consider what the aji is if descends instead of connecting.

I was first thinking of this... but seems to be wrong

Click Here To Show Diagram Code

[go]Bcm90
$$ | . . . O . . . . . . .
$$ | . O . . . . . . . . .
$$ | . O X X . . . . . , .
$$ | 2 X 3 . . X . O . . .
$$ | . O 1 . . . . . . . .
$$ | . 4 5 . . . . . . . .
$$ -----------------------[/go]

I suppose black would more do that , which leads to connect and die for white...

Click Here To Show Diagram Code

[go]Bcm90
$$ | . . . O . . . . . . .
$$ | . O . . . . . . . . .
$$ | . O X X . . . . . , .
$$ | 2 X 3 . . X . O . . .
$$ | 5 O 1 . . . . . . . .
$$ | 6 4 7 . . . . . . . .
$$ -----------------------[/go]

so maybe more something like that... it seems that "a" is good neither for black nor for white...

Click Here To Show Diagram Code

[go]Bcm90
$$ | . . . O . . . . . . .
$$ | . O . . . . . . . . .
$$ | . O X X . . . . . , .
$$ | 2 X 3 . . X . O . . .
$$ | 4 O 1 . . . . . . . .
$$ | a 5 . . . . . . . . .
$$ -----------------------[/go]

@oca: When Bill says 'descend' he means this:

Click Here To Show Diagram Code

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

In go, when talking directions, down is "towards the nearest edge" and up is "towards the center", hence descend here means "stretch towards the nearest (left) edge".

oh.. ok... thanks, I will rotate my brain by 90° and try again then...

Hi oca,

Click Here To Show Diagram Code

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

In addition to what Herman said,
the you made is a hane (on ),
and a tiger's mouth, but not a descend.
A descend is a solid extension toward and close to an edge.

Situations like these are made for database searches which can show you whole board positions in which a pro might play such a clamp and what might happen, afterwards.

Using this:
https://badukmovies.com/pro_games/pattern_search

... shows the move played here by Xiao Zhenghao, 6p...
https://badukmovies.com/pro_games/43703 ... an?move=85

... and here
https://badukmovies.com/pro_games/3079- ... hi?move=69

... and in some other pro. games.

Charlie wrote:Situations like these are made for database searches which can show you whole board positions in which a pro might play such a clamp and what might happen, afterwards.

Using this:
https://badukmovies.com/pro_games/pattern_search

... shows the move played here by Xiao Zhenghao, 6p...
https://badukmovies.com/pro_games/43703 ... an?move=85

... and here
https://badukmovies.com/pro_games/3079- ... hi?move=69

... and in some other pro. games.

Thanks.

The second game is not really an example that fits the diagram on SL, because it has a Black stone on the 6-7 point.

Bill Spight wrote: The second game is not really an example that fits the diagram on SL, because it has a Black stone on the 6-7 point.

Indeed. I was posting at work and my aim was to punt the idea of using a database search to find pro games in which a position arises. Those games were examples picked in a hurry.

Charlie wrote:

Bill Spight wrote: The second game is not really an example that fits the diagram on SL, because it has a Black stone on the 6-7 point.

Indeed. I was posting at work and my aim was to punt the idea of using a database search to find pro games in which a position arises. Those games were examples picked in a hurry.

Yes. Thanks, again.

HermanHiddema wrote:@oca: When Bill says 'descend' he means this:

B
$$ | . . . O . . . . . . .
$$ | . O . . . . . . . . .
$$ | . O X X . . . . . , .
$$ | 1 X . . . X . O . . .
$$ | . O . . . . . . . . .
$$ | . . . . . . . . . . .
$$ -----------------------

Click Here To Show Diagram Code

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

In go, when talking directions, down is "towards the nearest edge" and up is "towards the center", hence descend here means "stretch towards the nearest (left) edge".

Thanks, Herman.

First exercise.

Click Here To Show Diagram Code

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

What happens if White cuts?

@Charlie : thanks for the links, I didn't know that site.
@EdLee and Herman, thanks for your explanations, proper name is something important to me. I really like the proverb "If it has a name, know it" So I'm happy to add "descend" to my go vocabulary.

@Bill, thanks for the exercice,

I don't find any good continuation for white after that setup a ladder...

Click Here To Show Diagram Code

[go]B what for white after black 3...
$$ | . . . O . . . . . . .
$$ | . O . . . . . . . . .
$$ | . O X X . . . . . , .
$$ | 1 X 2 . . X . O . . .
$$ | . O 3 . . . . . . . .
$$ | . . . . . . . . . . .
$$ -----------------------[/go]

tryied

Click Here To Show Diagram Code

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

then at and that seems no good for white...
so I would not play ... correct ?

oca wrote:@Charlie : thanks for the links, I didn't know that site.
@EdLee and Herman, thanks for your explanations, proper name is something important to me. I really like the proverb "If it has a name, know it" So I'm happy to add "descend" to my go vocabulary.

@Bill, thanks for the exercice,

I don't find any good continuation for white after that setup a ladder...

B what for white after black 3...
$$ | . . . O . . . . . . .
$$ | . O . . . . . . . . .
$$ | . O X X . . . . . , .
$$ | 1 X 2 . . X . O . . .
$$ | . O 3 . . . . . . . .
$$ | . . . . . . . . . . .
$$ -----------------------

Click Here To Show Diagram Code

[go]B what for white after black 3...
$$ | . . . O . . . . . . .
$$ | . O . . . . . . . . .
$$ | . O X X . . . . . , .
$$ | 1 X 2 . . X . O . . .
$$ | . O 3 . . . . . . . .
$$ | . . . . . . . . . . .
$$ -----------------------[/go]

tryied

B
$$ | . . . O . . . . . . .
$$ | . O . . . . . . . . .
$$ | . O X X . . . . . , .
$$ | 1 X 2 5 . X . O . . .
$$ | . O 3 4 . . . . . . .
$$ | . . 6 . . . . . . . .
$$ -----------------------

Click Here To Show Diagram Code

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

then at and that seems no good for white...
so I would not play ... correct ?

Well done!

But the cut is a threat. What play or plays threaten the cut and also threaten something else? Play around with that.