Joseki, when to tenuki, when not, example 1
Let's take this familiar joseki as a first example:
After , Black can tenuki.
After , White cannot tenuki: a Black move around brings all her stones under severe attack.
Klaus: If white wants to play tenuki at this point, he should have played at a.
After , Black can tenuki, and a well known variation follows. The question is then whether Black's tenuki offsets the additional White thickness.
After , White can tenuki, her stone at can be treated lightly. Here too, the question is whether the tenuki is worth permitting the cut or any other destabilizing move. See 3-4 point high approach, inside contact, tenuki variation
After , Black cannot tenuki. White's atari at 4 would be too big a loss to justify the tenuki.
After , White cannot tenuki. Black's move at 5 next, makes 1-2 a bad exchange.
After , Black can tenuki, of course, because that reverts to a 3-4 approach to a 5-4 stone.
Klaus: Interesting overview! Do we have variations to jutify these statements somewhere at SL?
Klaus: Thanks, I started to add some links now.
I'd be interested to see other examples.
Grauniad: The main message of this page is apparently that when studying joseki it's important to analyze whether or not a player can tenuki after each move and if not why not. This analysis should be included with the description of the joseki. There are too many examples to include here. :-)
Charles Matthews This is certainly a helpful approach: though one can question absolute judgements here. The basic idea here is an 'oscillation of urgency' of the next play. If you add to that a comparison with the urgency of the most important play elsewhere, you get a fundamental picture: an oscillating graph with a horizontal line across it, dividing the tenuki region below from the 'don't play tenuki region' above.
(Often the temperature language is used here, but after previous discussion on SL I think we evolved a convention about using urgent for informal discussion, hot in relation to theoretical discussion.)
- Bill: We did? Anyway, urgent has a specific go meaning, just as hot has a specific CGT meaning. Informally they overlap. (Note that I have linked to a different page for urgent.)
The next point is about why there is oscillation. True believers in the temperature approach often think in terms of a 'trend line' according to which what you could call the urgency of big points decreases steadily during the game. For example in the endgame you have the gote plays that are taken in decreasing order, the game being spiced up with sente excursions for both sides that temporarily raise temperature.
The next question is, how useful is that thinking in the opening? Well, there are some cases of genuine sente plays in joseki, for example when a key group of stones is placed in atari and must be saved. But otherwise the 'sente-ness' of plays is subject to the kind of interrogation made here.
I'd say that one of the more useful explanations of what goes on is the Jim Kerwin remark quoted on One-Two-Three. Don't let your opponent make your plays look misplaced. In joseki that tends to say this: play tenuki early enough - don't play out too many moves and then decide to break off. The fewer moves you have played out, the less likely you are to have them made to look silly. That has to be balanced off against the forcing play aspect ( in the example).
Treating the other really common joseki in the same way:
Here is frequently omitted; and are somewhat more urgent (opinion has perhaps shifted on - see 4-4 point low approach low extension, tenuki); is more urgent again since it is generally the case that if White omits she should also have omitted , which takes away the option of invading instead at .
See also tenuki joseki: this page is more about ending early, while that is more about resumption.
For example, this tenuki development is standard in the context of a Shusaku fuseki.
Bill: It is also possible for White to omit the extension. White can respond at a to a pincer. Recently I saw an ancient game where there was neither an extension nor a pincer throughout the whole game! Rather, a moyo evolved.
Yes, for an ideal treatment of joseki, tenuki at each point would always be one of the variations. One can say, however, that
- there is never going to be an ideal, full treatment of joseki; and
- it's all a matter of strength, which tenuki lines are worth noting.
Sorry Charles, with the greatest respect, I'm going to have to differ from you.
For amateur players up to the highest levels, I strongly suspect that a simple-minded approach to the tenuki issue might in fact be best. That is, when one learns a joseki (as opposed to memorising it, of course), one should endeavour to know whether each play is necessary, as in the example Dieter provided. There are three basic paths:
a) Plays that are considered necessary
b) Plays that are good but where tenuki is possible
I assert that one should play moves of type "a" without hesitation, since the chances of gaining by playing tenuki are heavily outweighed by the chances of making a amateurish misjudgement of the exchange. Charles is surely right to point out the theoretical drawbacks of making such "absolute" judgements, but should anybody below pro level ever feel bad about playing a move that is always honte, and almost always urgent? It's probably a faster route to mastery to rely on moves that one knows are good instead of attempting furikawari judgements of the most difficult kind.
On the other hand, if one is faced with possibilities "b" and "c", one can apply positional judgement to make the selection.
Charles I think Tamsin is right from a didactic point of view. At least up at about 2 dan level. That is, mistakes coming from playing tenuki when you shouldn't will outweigh lost opportunities of playing tenuki when you can, perhaps for the bulk of amateurs. On the other hand one needs to develop flexible attitudes to become a strong amateur, and this is a prime example of what that means, in the way of being able to override 'template' thinking.
Dieter: Fully agree that one needs to override template thinking in order to rise to strong ama level. As a 3d I obviously write for people aiming to become strong kyus or to understand something better myself. The correcting diagram you give above drives home the idea very well. So cannot is probably too strong, even from a didactic point of view and with <2d audience in mind.
dnerra It might also be your opponent tenuki. In that case, a typical amateur reaction is "Now I have to punish the tenuki immediately." Needless to say, this can provoke overplays. Knowing that it is ok for your opponent to tenuki will help you judge the situation adequately and continue patiently.