Good Empty Triangle
Efficiency is one aspect of shape. Late in the game, especially, it can be obviously correct to make an empty triangle and making an empty triangle can also be the vital point. A good empty triangle is an instance of what the Japanese call guzumi.
Good empty triangles
Example 1 - Joseki (a)
makes "good shape" but becomes overconcentrated.
unkx80: I don't think it's so much about overconcentration. I believe that it's got more to do with destroying White's eye shape.
Bill: Well, it is a question of emphasis, isn't it? Anyway, let's take away the stone.
brindis: Just a question, why not 2 at 'a'?
This is fine for both players, no? Black does not need an extra stone.
Eagle : Tewari analysis may show that the black shape is overconcentrated, but i think in practice the second diagram is nothing worse than the first one (i think it's better , may be just because i missed something ) .It's worse than the third diagram,not the first diagram . Am i wrong ?
corwin: To my eyes, the biggest difference in the two diagrams is that black ends in sente in the first, and gote in the second.
Example - Joseki (b)
tderz: After the unreasonable cut , the continuation to
gives Black the miai of either a or b,
hence is a 'good empty triangle'. (source: Ishida a.o.)
Example - Joseki (c)
Example 2 - Tesuji
This problem comes from the Tesuji Dictionary, by Segoe Kensaku and Go Seigen. They say that if you get this one right, you are 5 dan. (Of course, you have a big hint. ;-))
Example 3 - Middle Game Joseki: "guzumi"
The sequence of to
is one of the best ways of escaping with the lone white stone at the top.
makes the empty triangle and then White has a rather clear exit, while aiming for the cutting point at a (at the correct time).
here would be a mistake.
plays at the vital point, destroying White's eye shape, and forcing
to connect with a bad empty triangle.
Bob McGuigan: Here's an example from one of my own games (I was Black) where Black responds to a White empty triangle move by making one too. White's empty triangle looks good but after Black's response ...
in response to
is good defense.
creates a cutting point in Black's shape.
takes a liberty from White and leaves a lot of aji against White's group.
tderz: Interesting position. (yet I think black's empty triangle is not necessary)
is tempting too - a & b seem miai now.
It is the same technique as in above joseki.
The white cut c seems far fetched with the created white weakness e.
If White wants to solidate first at at f, cutting through with black d would be possible
(resp. Bg, after white q, she cannot cut at r),
however, if replying with white d one has forced white to be very submissive (which is the intention of
) and could hane oneself with f.
Can White survive?
Yes, Wd - Be - Wg - Bf - then k (or l, smaller).
tderz: other ways for White to avoid an empty triangöle?
Perhaps not, after (protecting against the cut y) to
, there is still no connection to the left
, due to Black x (if Black a to white j have been exchanged),
but white cut capture at k and had no problems.
Theoretically, the black could become a target after
ot
, if Black tries too hard with black a to i?
Example 4 - forcing down
Example 5 - historic master games
Game Dosaku - Chitetsu, move 63
tderz: is a good empty triangle.
This a game with many local "tenukis" - ,
,
,
even in succession ! -
for keeping the initiative.
Acceptable empty triangle? - Hamete
tderz: from a Korean book, p.229 (ISBN 89-333-0346-4)
All black moves look completely natural, don't they? (except of course!)
Still he voluntarily created an empty triangle.
Should he have exchanged a for b first?
It's not so easy to decide on white's next move, hence the empty triangle can't be that bad and rather renamed fighting empty triangle.
Fighting empty triangle
Move 81 of the Blood Vomiting Game, diagram 6, move 7 on Senseis' page.
is the third ghost move. It is an example of a "bad shape/good move", and eventually allows Jowa to launch a difficult splitting attack that results in Black's resignation.
Normal Life & Death
Numerous problems are based on the empty triangle move which kills with a nakade shape.
(Therefore it is dangerous to tell beginners that an 'empty triangle is bad'.
One can tell them, that it is 'usually inefficient' - in the open field.
miaoshou, brilliant, excellent moves
![[Diagram]](../../diagrams/50/ab9f8f253b4b293a91d56f048ac739ea.png)
is the correct local endgame, afaik