Life In 19x19

I'm really enjoying your commentaries on these games. It's interesting that they are more concerned to make a base than today's players.

globulon wrote:I'm really enjoying your commentaries on these games. It's interesting that they are more concerned to make a base than today's players.

Well, I guess that's just the result of not having more advanced thinking about the opening. Making a base with miai was one of the best things they could see to do. In the second game White punished Black for playing a wedge on the top side instead of a pincer, but did either player see it that way?

We have seen that the ancients understood the importance of making a base in the opening, although they gave it too much importance. By the logic of discovery, it should be one of the first things taught about the opening.

The idea of a base is still quite important. When I was learning go, other amateurs explained the saying, Corners, sides, center, by pointing out it was easier to make territory in the corner than on the side, and easier to make territory on the side than in the center. However, Takagawa, in his Go Reader (IIRC), said that the reason was not so much about territory as that it is easiest to make a base in the corner and hardest to make one in the center.

What is a base? Like a lot of go terms, it does not seem to have a precise, generally accepted definition. The prototypical base is the two space extension on the side.

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[go]$$ Base
$$ . . . . . . . .
$$ . . X . . X . .
$$ . . . . . . . .
$$ . . . . . . . .
$$ ---------------[/go]

In Contemporary Go Terms Nam Chihyung says that a base can make two eyes if attacked. Obviously that is so for the two space extension on the side if the board is otherwise empty. And we would not call it a base if it were surrounded so that it was dead on arrival. I think that there are intermediate or unclear cases where we would still want to call it a base.

Now, one of the Nihon Kiin booklets that I bought when I was 4 kyu said that a base could not be cut in two (otherwise empty board assumed). That is obviously true for the two space extension.

Click Here To Show Diagram Code

[go]$$W Underneath connection
$$ . . . . . . . .
$$ . . X 1 3 X . .
$$ . . . 2 4 . . .
$$ . . . . . . . .
$$ ---------------[/go]

I don't remember all the variations in the booklet, but Black can easily connect underneath, as this diagram shows. Here is another variation.

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[go]$$W Underneath connection, ii
$$ . . . . . . . . .
$$ . . . 5 . . . . .
$$ . . X 1 4 X 9 . .
$$ . . 6 2 3 7 8 . .
$$ . . . . 0 . . . .
$$ -----------------[/go]

However, the underneath connection may be too passive, and the booklet showed connecting over the top.

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[go]$$W Over the top connection
$$ . . . . . . . . . . .
$$ . . 9 . . . . . . . .
$$ . 8 7 2 4 . 6 . . . .
$$ . . X 1 3 X . . . . .
$$ . . 0 . . 5 . . . . .
$$ . . . . . . . . . . .
$$ ---------------------[/go]

is necessary if White is to cut Black in two.

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[go]$$Wm11 Connection, continued
$$ . . . . . . . . . . .
$$ . . O . . . . . . . .
$$ . X O X X 2 X 9 . . .
$$ . . X O O X 1 5 8 . .
$$ . . X . 3 O 4 6 7 0 .
$$ . . . . . . . . . . .
$$ ---------------------[/go]

If Black plays at 17 she easily wins the semeai.

There are other variations, OC, but the message is clear. On an otherwise empty board a base cannot be cut in two.

Unfortunately, I assumed that, because a base could not be cut in two, I should never allow a base to be cut in two. That sometimes led to heavy play. The ancients knew better, as I will illustrate in the next post.

This is the famous game played in the Tang dynasty for a pair of gold petaled bowls.

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[go]$$Wc Kosumi
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . 6 7 . . . . . . . . . . . . . . |
$$ | . . . . . 1 . 2 . . . . . . . . . . . |
$$ | . . . X . . 3 4 . , . . . . . O . . . |
$$ | . . . . . . . 9 . . . . . . . . . . . |
$$ | . . . . . . 5 . . . . . . . . . . . . |
$$ | . . 8 . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

is unusual these days, but I suppose that the sequence up to was joseki back then.

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[go]$$Bcm10 Black base
$$ ---------------------------------------
$$ | . . . 6 . . . . . . . . . . . . . . . |
$$ | . . 4 X O . . . . . . . . . . . . . . |
$$ | . 7 . 5 . O . X . . 3 . 8 . . . . . . |
$$ | . . . X . . O X . , . . . . . O . . . |
$$ | . . . . . 1 2 O . . . . . . . . . . . |
$$ | . . . . . . O . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 9 . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

makes a base. approaches it. Since White is so strong in the area, you or I might have jumped out, but Black did not.

Click Here To Show Diagram Code

[go]$$Wcm19 Sacrifice
$$ ---------------------------------------
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . O X O . . . . 5 4 . . . . . . . . |
$$ | . X . X . O . B . 3 X . O . . . . . . |
$$ | . . . X . . O B . 1 2 . . . . O . . . |
$$ | . . . . . X O O . 7 6 . . . . . . . . |
$$ | . . . . . . O . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

attacks the Black group. at 21 would have been heavy. Instead, Black sacrificed the stones.

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[go]$$Bcm26 Counter invasion
$$ ---------------------------------------
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . O X O . . . . O X . 4 8 6 . . . . |
$$ | . X . X . O . X . O X . O 3 1 2 . . . |
$$ | . . . X . . O X . O X . 5 . . O . . . |
$$ | . . . . . X O O . O X . . . 7 . . . . |
$$ | . . . . . . O . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

Black uses the thickness built up by the sacrifice to invade White's base. White connects underneath while Black builds more thickness.

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[go]$$Bcm34 Black thickness
$$ ---------------------------------------
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . O X O . . . . O X . O O O . . . . |
$$ | . X . X . O . X . O X . O X X O . . . |
$$ | . . . X . . O X . O X . X 3 . O . 6 . |
$$ | . . . . . X O O . O X . 2 . X 1 5 4 . |
$$ | . . . . . . O . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . 7 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

The local skirmish continues. plays kikashi, forcing Black to make an empty triangle. is tesuji, as well.

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[go]$$Wcm41 A vulnerable base
$$ ---------------------------------------
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . O X O . . . . O X . O O O . . . . |
$$ | . X . X . O . X . O X . O X X O . . . |
$$ | . . . X . . O X . O X . X X . O . O . |
$$ | . . . . . X O O . O X . O . X X X O . |
$$ | . . . . . . O . . . . . . . . . . 2 . |
$$ | . . X . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 1 . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 3 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . 4 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

White makes a base on the right side, but, since it is so close to Black's thickness, it is vulnerable to attack.

Click Here To Show Diagram Code

[go]$$Bcm70 Attack
$$ ---------------------------------------
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . O X O . . . . O X . O O O . . . . |
$$ | . X . X . O . X . O X . O X X O . . . |
$$ | . . . X . . O X . O X . X X . O . O . |
$$ | . . . . . X O O . O X . O . X X X O . |
$$ | . . . . . . O . . . . . . . . . . X . |
$$ | . . X . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . X , . . . . . , . . . . . , 3 1 . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . . . . . . . . . . . . . . O . . |
$$ | . X O O . . . . . . . . . . . . 2 . . |
$$ | . X X . O . O . . . . . . . . . X . . |
$$ | . . O . . X O . . . . . O . . . . . . |
$$ | . . . O O O X . . , . . . . . X . . . |
$$ | . . . . O X X . X . X . O . X . . . . |
$$ | . . . . O X . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

The attack comes with . White counters with , allowing .

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[go]$$Wcm73 Counterattack
$$ ---------------------------------------
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . O X O . . . . O X . O O O . . . . |
$$ | . X . X . O . X . O X . O X X O . . . |
$$ | . . . X . . O X . O X . X X . O . O . |
$$ | . . . . . X O O . O X . O . X X X O . |
$$ | . . . . . . O . . . . . . . . . . X . |
$$ | . . X . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . X , . . . . . , . . . . . , X X . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . . . . . . . . . . . . . . O . . |
$$ | . X O O . . . . . . . . . . . . O . 7 |
$$ | . X X . O . O . . . . . . . . . B 1 . |
$$ | . . O . . X O . . . . . O . . . 2 3 6 |
$$ | . . . O O O X . . , . . . . . B . 4 . |
$$ | . . . . O X X . X . X . O . B . 5 . . |
$$ | . . . . O X . . . . . . . O . . 8 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

White plays a counterattack against the Black corner. Will we ever look at the stones the same way again? is tesuji.

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[go]$$Wcm81 Run, run
$$ ---------------------------------------
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . O X O . . . . O X . O O O . . . . |
$$ | . X . X . O . X . O X . O X X O . . . |
$$ | . . . X . . O X . O X . X X . O . O . |
$$ | . . . . . X O O . O X . O . X X X O . |
$$ | . . . . . . O . . . . . . . . . . X . |
$$ | . . X . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . X , . . . . . , . . . . . , X X . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . . . . . . . . . . . 9 . . O . . |
$$ | . X O O . . . . . . . . . . . . O . O |
$$ | . X X . O . O . . . . . . 8 . . X O . |
$$ | . . O . . X O . . . . . O . . . X O X |
$$ | . . . O O O X . . , . . . . . X . X . |
$$ | . . . . O X X . X . X . O . X 6 O 4 . |
$$ | . . . . O X . . . . . . . O 2 1 X 3 . |
$$ | . . . . . . . . . . . . . . 5 . 7 . . |
$$ ---------------------------------------[/go]

Both sides run out into the center.

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[go]$$Bcm90 Twining attack
$$ ---------------------------------------
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . O X O . . . . O X . O O O . . . . |
$$ | . X . X . O . X . O X . O X X O . . . |
$$ | . . . X . . O X . O X . X X . O . O . |
$$ | . . . . . X O O . O X . O . X X X O . |
$$ | . . . . . . O . . . . . . . . . . X . |
$$ | . . X . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . X , . . . . . , . . . . . , X X . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . . . . . . . . . . . O 2 4 O . . |
$$ | . X O O . . . . . . . 7 . 1 . 3 O . O |
$$ | . X X . O . O . . . . . . X . . X O . |
$$ | . . O . . X O . . . 0 . O . . . X O X |
$$ | . . . O O O X . . , . 5 6 . . X . X . |
$$ | . . . . O X X . X . X . O . X X O X . |
$$ | . . . . O X . . . 8 9 . . O X O . O . |
$$ | . . . . . . . . . . . . . . O . O . . |
$$ ---------------------------------------[/go]

pushes out in a twining attack against both White groups. is tesuji, an excellent sacrifice that allows the White corner group to escape.

Click Here To Show Diagram Code

[go]$$Bcm130 The battle ends
$$ ---------------------------------------
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . O X O . . . . O X . O O O . . . . |
$$ | . X . X . O . X . O X . O X X O . . . |
$$ | . . . X . . O X . O X 3 X X . O . O . |
$$ | . . . . . X O O . O X . O . X X X O . |
$$ | . . . . . . O . . . O 2 . . . . . X . |
$$ | . . X . . . . . . . . . . . . . X . . |
$$ | . . 4 . . . . . . X O O O X . . . . . |
$$ | . . . . . . . . 1 . X X O . X X O X . |
$$ | . . X , . . . . . , . . O O O O X X . |
$$ | . . . . . . . . . . . X X . . . . . . |
$$ | . X . . . . . . . X . X O O O O O . . |
$$ | . X O O . . . X X O . X . X . X O . O |
$$ | . X X . O . O O O O . X . X . . X O . |
$$ | . . O . . X O . . . O O O . . . X O X |
$$ | . . . O O O X . . X . X O . . X . X . |
$$ | . . . . O X X . X . X . O . X X O X . |
$$ | . . . . O X . . . O X . . O X O . O . |
$$ | . . . . . . . . . . . . . . O . O . . |
$$ ---------------------------------------[/go]

The battle finally ends at move 132. Then White opens a new front with an invasion of the left side.

The ancients had excellent reading and fighting skills.

A quick note today about my discovery of the theme of the base in ancient openings.

Everyone these days knows about corners, sides, center, but it is really a modern idea, and one that was challenged by the New Fuseki. Also, it is plain that ancient players often valued sides more than corners at various points in the opening, although it has nearly always been rare to place the first stone on the side. In the games we have looked at (with the corners already occupied by setup stones) one of the first things players did was to make a base on the side.

It has seemed to me that players today are stressing the sides more than they did when I was learning go. With that in the back of my mind I noticed that players in the early modern era (17th century) often made a specific base on the side, on the 3-8 and 3-11 points.

Click Here To Show Diagram Code

[go]$$W Common base (17th century)
$$ -----------
$$ . . . . . .
$$ . . . . . .
$$ . X . . X .
$$ . . . , . .[/go]

I have not done a study of that base, but it still occurs today, although not very frequently. We have seen it in these very ancient games when a player played on the 3-11 point with the 3-8 point as a miai point to make a base. In the early modern era players often made the base with no provocation at all. OC, making this base would usually be slow by today's standards.

I have not done a study of that base, but it still occurs today, although not very frequently. We have seen it in these very ancient games when a player played on the 3-11 point with the 3-8 point as a miai point to make a base. In the early modern era players often made the base with no provocation at all. OC, making this base would usually be slow by today's standards.

I have to disagree on a couple of points.

Not sure what you mean exactly by early modern era, but whatever the cut-off, until the late 20th century players made many moves in consideration of there being no komi, so they may not have been making this shape gratuitously.

More important, this shape is nowhere near as rare as you seem to think today. Taking a generous space, with a third-line two-space extension centred inside an otherwise empty 10x5 rectangle of points based on the sides (to attenuate the charge of provocation from nearby stones), roughly 80% of well over 1,000 games in the GoGoD database that have this pattern can be classed as modern, taking as an arbitrary cut-off point the advent of Go Seigen. Even if you want to restrict it to very recent years it is still very common, and appears without any obvious bias in all the major pro countries and with the usual cast of stars.

If you are counting early Edo as "early modern", with one exception the shape does not appear before 1620 (Dosaku) and is not specially common thereafter in early Japan. It is the Chinese who played it most then.

If you make the rectangle 8x5, it's ten times more common (almost 15% of all games) and even more so in modern play. Making the cut-off date here equally arbitrary at 1980, 75% of cases are in modern games (Sansa still gets just one).

Not every case can be classed as a base pure and simple, but plenty can (most? - over 90% of cases occur in the first 50 moves), and of course even extensions from a moyo can be cut off and have to fend for themselves.

It's more the third line and pincer width that differentiate the ancients from the moderns rather than two-space bases (see also Fukui Masaaki on this topic).

John Fairbairn wrote:

I have not done a study of that base, but it still occurs today, although not very frequently. We have seen it in these very ancient games when a player played on the 3-11 point with the 3-8 point as a miai point to make a base. In the early modern era players often made the base with no provocation at all. OC, making this base would usually be slow by today's standards.

I have to disagree on a couple of points.

Not sure what you mean exactly by early modern era, but whatever the cut-off, until the late 20th century players made many moves in consideration of there being no komi, so they may not have been making this shape gratuitously.

More important, this shape is nowhere near as rare as you seem to think today. Taking a generous space, with a third-line two-space extension centred inside an otherwise empty 10x5 rectangle of points based on the sides (to attenuate the charge of provocation from nearby stones), roughly 80% of well over 1,000 games in the GoGoD database that have this pattern can be classed as modern, taking as an arbitrary cut-off point the advent of Go Seigen.

Thanks, John. I was talking specifically about the 3-8, 3-11 base, while you seem to be talking about bases on the side in general. I could still be mistaken about its incidence, however.

It shows up with setup stones in exchanges such as this.

Click Here To Show Diagram Code

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

I think that this sequence would be quite rare these days.

Edit: In fact, given that the idea of a base is fundamental opening knowledge, it would be surprising if they were not common.

Bill, that precise shape only occurs 11 times, all Chinese, all very ancient, and at a time when group tax still applied. The importance of connectivity therefore might have been more important than its value as a base.

John Fairbairn wrote:Bill, that precise shape only occurs 11 times, all Chinese, all very ancient, and at a time when group tax still applied. The importance of connectivity therefore might have been more important than its value as a base.

Thanks, John. Good point about the group tax.

In another game the 3-8, 3-11 base occurs twice: The famous "Four Immortal meet in Chengdu" game, dated 1094.

Click Here To Show Diagram Code

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

is a wedge with miai to make a base.

Click Here To Show Diagram Code

[go]$$Bcm19 Another wedge
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 2 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 1 . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . X . . . . . . . . . . . 3 . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . O X . . . . . . . . . . . . O . . |
$$ | . . O X . X . . . . . . . . . . . . . |
$$ | . . . O X . . . . , . . . . . X . . . |
$$ | . . O . O X . O . . O . X . . . . . . |
$$ | . . . . O X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

Ditto for .

The 3-8, 3-11 base has never disappeared, but it may be making a resurgence, along with the 3-11 wedge, as players emphasize the sides more. Here is one example, dated Feb. 28, 2013, among several in recent years.

Click Here To Show Diagram Code

[go]$$Bc Takemiya (W) - Yuki Satoshi
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . 4 . . . . . , . . . . 5 , 1 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 8 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . 6 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 7 . . |
$$ | . . . 2 . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . 3 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

White plays the wedge, , allowing Black to make a second enclosure with . Then makes a base.

Click Here To Show Diagram Code

[go]$$Bc Takemiya (W) - Yuki Satoshi
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . 4 . . . . . , . . . . 5 , 1 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 8 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . 6 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 7 . . |
$$ | . . . 2 . . . . . a . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . 3 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

But wouldn't 3, 7 and a be good shape for Black? White playing the wedge at basically lets Black get that shape.

Fedya wrote:

$$Bc Takemiya (W) - Yuki Satoshi
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . 4 . . . . . , . . . . 5 , 1 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 8 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . 6 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 7 . . |
$$ | . . . 2 . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . 3 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------

Click Here To Show Diagram Code

[go]$$Bc Takemiya (W) - Yuki Satoshi
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . 4 . . . . . , . . . . 5 , 1 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 8 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . 6 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 7 . . |
$$ | . . . 2 . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . 3 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

But wouldn't 3, 7 and a be good shape for Black? White playing the wedge at basically lets Black get that shape.

Yup. That's why wasn't played much for a long time. But it seems to be coming back into style.

I may be misunderstanding where you are going with this, Bill, but again I don't think the figures are bearing out what you are saying about commonness, modernness or resurgences.

In the specific fuseki you show, the R9 wedge (your 3-11) is rare - just 5 cases and all since 2000. Overwhelmingly, in that position White does not wedge but plays a kakari.

If you strip out the left-side White stones, the right side is still not hugely common - about 500 cases ever, and the wedge still appears only in 10% of cases.

The Black shimari has some effect. The Black shape with small knight's move shimari is some 8 times more common, but then the incidence of the wedge drops to about 5%. I assume we can infer that White is hoping to do something a bit more specific against the high shimari than just making a base. This seems supported by the fact that the incidence of White R9 against a Black shimari with a large knight's move is also very close to that with the small knight's move. Agreed, though, that the more specific bit must include something to do with stressing the side.

You mention Takagawa a lot in this connection. My memory on this is vague but I think I too can recall him talking about the wedge a lot - but only in theory. If so, I wonder whether you have got a wrong idea of frequency from that and are talking more about examples in captivity rather than in the wild.

I haven't forgotten you, John. It's just that I anticipate making an extended reply.

One thing quickly. IMO, the idea of a base is one of the fundamentals of the opening. My reference to Takagawa is in support of that.

Another thing, the 3-8, 3-11 base is a minor theme. I noticed it in 17th century openings, and was surprised to find it in very ancient openings, as well.