Different pinchers after approaching 4-4

gostudent · #1

I am trying to understand the differences between different pinchers on a low approach to a 4-4 stone. Of course, there are many scenarios where pincher would be wrong, e.g. when the pincher stone would be easily attacked. For simplicity, let's assume that pincher is a reasonable move. There are six choices:

Click Here To Show Diagram Code: [go]$$ $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . O . a c e . . . . . . . . . | $$ | . . . X . . . b d f . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . |[/go]

I am under the impression that one-space-low-pincher (a) and two-space-high-pincher (d) are most common. Am I correct? If that is the case, why one-space-high-pincher (b) and two-space-low-pincher (c) are rarely played? Also, what might be some scenarios that would call for three-space pinchers (e and f)?

With respect to the comparison between (a) and (d): I have come up with the following. It seems that, not surprisingly, that low pincher is more severe, and high pincher has better influence. Please let me know if I've made any mistakes, or if there is any other important differences that I have missed.

(i) White can choose to press the one-space-low-pincher stone to build influence, but that would give black a lot of territory. White cannot do that on the two-space-high-pincher stone.

Click Here To Show Diagram Code: [go]$$ $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . O . 1 7 9 . a . . . . . . . | $$ | . . . X . . . 5 4 8 0 . . . . , . . . | $$ | . . . . . 2 . 6 . . . . . . . . . . . | $$ | . . . 3 . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . |[/go]

(ii) Two-space-high-pincher stone would make white easier to live, whereas one-space-low-pincher is more severe, and living locally is more difficult. (Yes, W4 for one space pincher is typically not good because it ruins entering 3-3, but I include that for comparison.)

Click Here To Show Diagram Code: [go]$$B $$ ------------------------------------------- $$ - . . . . . . . . . . . - . . . . . . . . . $$ - . . . 4 . . . . 6 . . - . 7 6 4 . . . . . $$ - . . 5 . . O . . 8 . . - . . 5 . . O . 1 . $$ - . . . X . . . . 1 . . - . . . X . . . . . $$ - . . . . . 2 . . . . . - . . . . . 2 . . . $$ - . . . 3 . . . . . . . - . . . 3 . . . . . $$ - . . . . . 7 . . . . . - . . . . . . . . . $$ - . . . . . . . . . . . - . . . . . . . . . $$ - . . . . . . . . . . . - . . . . . . . . .[/go]

(iii) White is more likely to tenuki facing the two-space-high-pincher, since there is more aji left of his stone:

Click Here To Show Diagram Code: [go]$$B $$ ------------------------------------------- $$ - . . . . . . . . . . . - . . . . . . . . . $$ - . . . . . . . . . . . - . . . . . . . . . $$ - . . . . . O . . . . . - . . . . . O . 1 . $$ - . . . X . 3 . . 1 . . - . . . X . 3 . . . $$ - . . . . . . . . . . . - . . . . . . . . . $$ - . . . . . . . . . . . - . . . . . . . . . $$ - . . . . . . . . . . . - . . . . . . . . . $$ - . . . . . . . . . . . - . . . . . . . . . $$ - . . . . . . . . . . . - . . . . . . . . .[/go]

(iv) If white chooses to enter 3-3, it is often okay for black to ignore the approach stone for one-space-low-pincher, but the risk for ignoring is higher for two-space-high-pincher. (I assume the direction of blocking; the sente issue here would not matter if the blocking is the other way.)

Click Here To Show Diagram Code: [go]$$B $$ ------------------------------------------- $$ - . . . . . . . . . . . - . . . . . . . . . $$ - . . O O X . . . . . . - . . O O X . . . . $$ - . . O X X O . . . . . - . . O X X O . X . $$ - . . O X . 1 . . X . . - . . O X . . . . . $$ - . . . X . . . . . . . - . . . X . . . . . $$ - . . O . . . . . . . . - . . O . . . . . . $$ - . . . . . . . . . . . - . . . . . . . . . $$ - . . . . . . . . . . . - . . . . . . . . . $$ - . . . . . . . . . . . - . . . . . . . . .[/go]

(v) If white approaches from another direction, the following are two possible variations. The low pincher allows black to cut immediately after W2, and black ends up with a more "territorial" position. Black can also skip B7 to get sente. On the other hand, the high pincher doesn't give black a base, allows white to live bigger, but the marked white stone is also damaged, and thus black seems to have better influence.

Click Here To Show Diagram Code: [go]$$B $$ ------------------------------------------- $$ - . . . . . . . . . . . - . . . . . . . . . $$ - . . 6 . . . . . . . . - . . . . . . . . . $$ - . . . . 4 O 8 . . . . - . . 6 . 5 O 3 X . $$ - . . . X . 1 2 . X . . - . . 4 X . 1 2 . . $$ - . . . 5 . 3 7 . . . . - . . . . . 7 . . . $$ - . . . W . . . . 9 . . - . . . O . . . . . $$ - . . . . . . . . . . . - . . . . . . . . . $$ - . . . . . . . . . . . - . . . . . . . . . $$ - . . . . . . . . . . . - . . . . . . . . .[/go]

oca · #2

That one is also interessting I think...

Click Here To Show Diagram Code: [go]$$B or 2 at a $$ +-------------------- $$ | . . . . . . . . . . $$ | . . . . . . . . . . $$ | . . . . . O . 1 . . $$ | . . . X . . . . . , $$ | . . . . . . . . . . $$ | . . 2 a . . . . . . $$ | . . . . . . . . . . $$ | . . . . . . . . . . $$ | . . . . . . . . . . $$ | . . . , . . . . . ,[/go]

Uberdude · #3

Btw, it's pincer not pincher.

Most of what you said is ok, though I would say that adding a move to quell the approach stone is not normal for 2-space high after white takes the corner. It's really only the 3 space ones where such a move is not too slow. Also if you tenuki the 2 space high pincer probably kick rather than attach is the followup.

Another important general point is the closer the pincer the less space it has (and thus more pressure it is under) if white jumps out and then counter pincers.

Bill Spight · #4

Uberdude wrote:

Btw, it's pincer not pincher.

According to Webster's, the Anglo-French verb, pincer (also spelled pincher) meant to pinch.

John Fairbairn · #5

Quote:

Btw, it's pincer not pincher.

While accepting that is the norm in go literature I feel impelled - as a fellow UK citizen - to point out that pincher was the normal word when I was young in the north of England, and I'm apt to use it to this day for a pair of pinchers, or a crab's claws.

Since it was usual also to regard southerners in general as a bunch of pansies, I have this peculiar trait now in that I regard pincher as a manly word and pincer as en effete "southron" word. Probably influenced by the phrase "pincer movement", I also regard a pincer as a somewhat remote, strategic move, whereas a pincher would imply a clamp, a tactical move. As has been discussed on this forum recently, you can't really control what your subconscious gets up to

Japanese has the same dilemma, i.e. hasami can refer to a strategic pincer and a clamp, but in recent times they have tended to make a distinction by using hasamatsuke for the clamp.

Krama · #6

Is there any guide to pincers? Without going into complicated reading and learning of every single vartiation.

paK0 · #7

Krama wrote:

Is there any guide to pincers? Without going into complicated reading and learning of every single variation.

Yilun Yang: The Fundamental Principles of Go

There are about 5 pages in it about pincers that cover the basic principles, though like most other joseki, they boil down to: "Look at the whole board"

Joaz Banbeck · #8

Herman Hiddema wrote a good post on pincers: http://www.lifein19x19.com/forum/viewto ... 837#p40837

S2W · #9

Dwyrin has a recent lecture on pincers: http://youtu.be/HXBDIzpO5BM

gostudent · **#10**

Thank you for all your reply. I still have one question, though:

I am under the impression that one-space-low-pincer (a) and two-space-high-pincer (d) are most common. Am I correct? If that is the case, why one-space-high-pincer (b) and two-space-low-pincer (c) are rarely played?

Why are one-space-high and two-space-low not played frequently?

Uberdude · **#11**

gostudent wrote:

I am under the impression that one-space-low-pincer (a) and two-space-high-pincer (d) are most common. Am I correct? If that is the case, why one-space-high-pincer (b) and two-space-low-pincer (c) are rarely played?

Why are one-space-high and two-space-low not played frequently?

Yes one-space low is most common and two-space high next. I don't know why one-space high is less common other than some cop-out answer like there are fewer board positions where it leads to a good position. One idea is it allows white to jump and then slide to the corner and under it, to settle on the side, which the low doesn't, and giving your opponent more options is usually bad. Also if white takes the corner it can end up rather close, a further pincer could have a better relationship with the rest of the board, or low would mean there is less aji left in the approach stone. As for two-space low, when I started playing it was regarded as not really a joseki, because if white takes the corner it's too slow to add a move to suppress the approach stone, but bad aji not to. But recently it's become popular again in situations where it is a big extension:

Click Here To Show Diagram Code: [go]$$W $$ +---------------------------------------+ $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . . . . . , . . . . . X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . 1 . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . 2 . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . . . . . , . . . . . , X . . | $$ | . . . . . . . . . . . . . . X . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ +---------------------------------------+[/go]

That's because it white takes the corner, black is not so worried about white activating the approach stone because doing so enlarges and strengthens black's lower right moyo (maybe black played a-b-c after white took the corner in gote):

Click Here To Show Diagram Code: [go]$$W $$ +---------------------------------------+ $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . O . O O O . | $$ | . . . O . . . . . , . . . . X X X O . | $$ | . . . . . . . . . . . . . . . . X X . | $$ | . . . . . . . . . . . . . . . . O . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . 1 . . | $$ | . . . . . . . . . . . . . . . 2 X . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . b . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . . . . . c . . . . . , X . . | $$ | . . . . . a . . . . . . . . X . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ +---------------------------------------+[/go]

skydyr · **#12**

paK0 wrote:

Krama wrote:

Is there any guide to pincers? Without going into complicated reading and learning of every single variation.

Yilun Yang: The Fundamental Principles of Go

There are about 5 pages in it about pincers that cover the basic principles, though like most other joseki, they boil down to: "Look at the whole board"

Beyond very basic principles, I fear a lot of it is on the lines of "here are a bunch of continuations from this pincer, make sure you can force all of them to turn out acceptably for you at the least." Followed by "here are a bunch of continuations from all the other pincers, and side plays. Make sure you can't force a better result using a different one."

That said, in general there is a tradeoff between tightness/severity/more easily counterattacked and looseness/less severity/less possibility of counterpressure. High vs low often boils down to high to keep your opponent smaller and take influence, low to keep them from settling as easily. You don't see loose low pincers as much with the 4-4 stone because the pincered stone can always trade for the corner or take some of the corner to help get a base, so it's often not forceful enough unless it builds an existing position on the other side, and it doesn't use the 4-4 stone as much.

Also sometimes (like with 5-3 stones) high pincers imply that you want to build on the side of the 5-3 stone, and low pincers that you want to build on the side of the pincering stone.

More specifically, most if not all of the pincers also have common lines where your opponent gives up a little in order to change the direction back to a more favourable one, or otherwise frustrate your ambitions. The 4-4, knight's move approach, one space low pincer, one space jump is one example of this. Traditionally it was regarded as inferior to taking the corner, but it's good to limit influence if taking the corner would give too much. Recently, the double approach in that line that oca posted has also become more common, to frustrate the opponent in a different way, one example being when they might want to play this and white feels that sente isn't enough:

Click Here To Show Diagram Code: [go]$$Wc $$ ------------------ $$ | . . . . . . . . . $$ | . . . . . 5 . . . $$ | . . 1 3 . O . X . $$ | . . 2 X 4 . . . . $$ | . . . . . . 6 . . $$ | . . . . . . . . . $$ | . . . . . . . . . $$ | . . . . . . . . . $$ | . . . . . . . . . $$ | . . . X . . . . .[/go]

As another example, this is a pretty common line, but in this situation:

Click Here To Show Diagram Code: [go]$$c White can cause trouble in the other corner in sente. $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . O . X 5 7 . 9 . . . . 0 . . | $$ | . . . X . . . 3 2 6 8 . . . . X . . . | $$ | . . . . . O . 4 . . . . . . . . . . . | $$ | . . . 1 . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . |[/go]

So it's better in this case to play a different line:

Click Here To Show Diagram Code: [go]$$c White doesn't have the same scope to cause trouble in the top right,\n and ends in gote, but his position is more solid.\nOn the other hand, black's top left is much more secure. $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . 5 . . . . . . . . . . . . . | $$ | . . . . 3 O 6 X 4 . . . . . . . . . . | $$ | . . . X . . . . 2 , . . . . . X . . . | $$ | . . . . . O . . . . . . . . . . . . . | $$ | . . 1 . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . |[/go]

There is also ladder aji in these lines, starting from here:

Click Here To Show Diagram Code: [go]$$c If black can fight through the hair-raising variations from here, then white\nhad better be able to ladder out or he collapses. $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . O . X . . . . . . . . . . . | $$ | . . . X . . . 3 2 , . . . . . , . . . | $$ | . . . . . O . 4 5 . . . . . . . . . . | $$ | . . . 1 . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . |[/go]

Unfortunately, you usually learn things like this the hard way, by losing games when your opponent knows how to punish. Even "simple" joseki can hide terribly complicated variations beneath their surface that aren't the best to play, provided you can read 15-20 moves ahead to see how one side loses the capturing race through this or that tesuji. Fortunately, there's no shame in it, because they probably learned to punish it by losing to it as well. I know I did :oops:

Different pinchers after approaching 4-4

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