Invasion or approach?

General conversations about Go belong here.
Post Reply
User avatar
Knotwilg
Oza
Posts: 2432
Joined: Fri Jan 14, 2011 6:53 am
Rank: KGS 2d OGS 1d Fox 4d
GD Posts: 0
KGS: Artevelde
OGS: Knotwilg
Online playing schedule: UTC 18:00 - 22:00
Location: Ghent, Belgium
Has thanked: 360 times
Been thanked: 1021 times
Contact:

Invasion or approach?

Post by Knotwilg »

Click Here To Show Diagram Code
[go]$$W Invasion or approach
$$ ---------------------
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .
$$ | . . 1 . . . . . . .
$$ | . . . , . . . . . .
$$ | . . . B . . . . . .
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .[/go]
When BB is on the 5-4 point, do we consider :w1: an invasion or an approach?
Click Here To Show Diagram Code
[go]$$W Invasion or approach
$$ ---------------------
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .
$$ | . . . 1 . . . . . .
$$ | . . . , . . . . . .
$$ | . . . B . . . . . .
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .[/go]
Same question
Click Here To Show Diagram Code
[go]$$W Invasion or approach
$$ ---------------------
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .
$$ | . . . 1 . . . . . .
$$ | . . . , . . . . . .
$$ | . . B . . . . . . .
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .[/go]
Same question
Click Here To Show Diagram Code
[go]$$W Invasion or approach
$$ ---------------------
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .
$$ | . . 1 . . . . . . .
$$ | . . . , . . . . . .
$$ | . . B . . . . . . .
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .
$$ | . . . . . . . . . .[/go]
Same question
User avatar
Harleqin
Lives in sente
Posts: 921
Joined: Sat Mar 06, 2010 10:31 am
Rank: German 2 dan
GD Posts: 0
Has thanked: 401 times
Been thanked: 164 times

Re: Invasion or approach?

Post by Harleqin »

What's the difference? What decision does the choice of words affect?
A good system naturally covers all corner cases without further effort.
User avatar
ez4u
Oza
Posts: 2414
Joined: Wed Feb 23, 2011 10:15 pm
Rank: Jp 6 dan
GD Posts: 0
KGS: ez4u
Location: Tokyo, Japan
Has thanked: 2351 times
Been thanked: 1332 times

Re: Invasion or approach?

Post by ez4u »

It seems that you revised all the page names at SL before asking this question. So why don't you go ahead and explain your reasoning? :)
Dave Sigaty
"Short-lived are both the praiser and the praised, and rememberer and the remembered..."
- Marcus Aurelius; Meditations, VIII 21
skydyr
Oza
Posts: 2495
Joined: Wed Aug 01, 2012 8:06 am
GD Posts: 0
Universal go server handle: skydyr
Online playing schedule: When my wife is out.
Location: DC
Has thanked: 156 times
Been thanked: 436 times

Re: Invasion or approach?

Post by skydyr »

In the absence of other local stones, I would call them approaches. From a strictly taxonomic perspective I'm reluctant to call playing 3-3 under a lone 4-4 stone early on an invasion, but I realize it's accepted usage. I think in that case, the word invasion comes from the fact that until recently it was generally played quite late.

Perhaps, in my mind at least, an invasion is a middle-game phenomenon to be contrasted with a reduction, rather than an approach. Some of the confusion probably comes from the overloaded meaning of approach as both 'get close to a position' and 'make the second move in a corner area'.
Kirby
Honinbo
Posts: 9553
Joined: Wed Feb 24, 2010 6:04 pm
GD Posts: 0
KGS: Kirby
Tygem: 커비라고해
Has thanked: 1583 times
Been thanked: 1707 times

Re: Invasion or approach?

Post by Kirby »

If the examples here aren't approaches, I don't know what moves would be. Maybe the argument is that we don't need the term. Not sure if that's true or not.
be immersed
User avatar
Knotwilg
Oza
Posts: 2432
Joined: Fri Jan 14, 2011 6:53 am
Rank: KGS 2d OGS 1d Fox 4d
GD Posts: 0
KGS: Artevelde
OGS: Knotwilg
Online playing schedule: UTC 18:00 - 22:00
Location: Ghent, Belgium
Has thanked: 360 times
Been thanked: 1021 times
Contact:

Re: Invasion or approach?

Post by Knotwilg »

ez4u wrote:It seems that you revised all the page names at SL before asking this question. So why don't you go ahead and explain your reasoning? :)
I did on request by user bugcat and then had second thoughts. So it's "work in progress". I'm relatively indifferent.
User avatar
Knotwilg
Oza
Posts: 2432
Joined: Fri Jan 14, 2011 6:53 am
Rank: KGS 2d OGS 1d Fox 4d
GD Posts: 0
KGS: Artevelde
OGS: Knotwilg
Online playing schedule: UTC 18:00 - 22:00
Location: Ghent, Belgium
Has thanked: 360 times
Been thanked: 1021 times
Contact:

Re: Invasion or approach?

Post by Knotwilg »

Harleqin wrote:What's the difference? What decision does the choice of words affect?
Well, some of us do care about the choice of words.

In some cases the discussion is pointless, in many cases the chosen word reflects a thought.

In this case, thinking about it as an "invasion" means you expect some pressure from the one "invaded" where the "invader" can expect to live, at the expense of major thickness and probably sente. An "approach" would mean both sides can expect a fair share of both territory, influence/thickness and sente, and the share depends on choices along the way. An "invasion" can't really expect to come out with all or the bigger part of the outward thickness.

And this probably answers my own question. I'd like to have your opinion too.

-- BTW I didn't expect the sarcasm or even hostility with which the question was met.
John Fairbairn
Oza
Posts: 3724
Joined: Wed Apr 21, 2010 3:09 am
Has thanked: 20 times
Been thanked: 4672 times

Re: Invasion or approach?

Post by John Fairbairn »

Well, some of us do care about the choice of words.
Pause for irony...
-- BTW I didn't expect the sarcasm or even hostility with which the question was met.
As a native speaker, I see absolutely no sarcasm or hostility or other forms of contumely in any of the replies. Not a hint, not touch, not a sausage, not a whisper, not a fig.

But given previous discussions on uchikomi/invasion, I can well see why some readers seek clarifications.

The 3-3 play in the corner is usually called uchikomi in Japanese. The other moves never are. They are kakari. Some of us think of what you call 'approach' as kakari, the Japanese term, which doesn't mean approach, at least in the meaning we probably first associate with that word. The Japanese sense is seeking a handhold, tegakari ('te' punning on hand and move, of course), and it has connotations of looking for clues. That is, it is a kind of probe. It therefore implies a range of possible replies by the opponent. In contrast a 3-3 play has very limited possibilities, and it is more of precisely directed hammer blow (i.e. uchikomi).

As you say, the words each reflect a different thought, and it is useful to acknowledge that fact. However, invasion reflects a different thought from uchikomi, and kakari reflects a different thought from approach (and yose reflects a different thought from endgame, etc etc etc). Given these two parallel universes, it seems natural for readers to find out which universe you want us to be in. No?

And no, I'm not being sarcastic either. Semiology is too important a topic in go to take lightly.
User avatar
Harleqin
Lives in sente
Posts: 921
Joined: Sat Mar 06, 2010 10:31 am
Rank: German 2 dan
GD Posts: 0
Has thanked: 401 times
Been thanked: 164 times

Re: Invasion or approach?

Post by Harleqin »

No sarcasm nor hostility intended, honestly.
Knotwilg wrote: In this case, thinking about it as an "invasion" means you expect some pressure from the one "invaded" where the "invader" can expect to live, at the expense of major thickness and probably sente. An "approach" would mean both sides can expect a fair share of both territory, influence/thickness and sente, and the share depends on choices along the way. An "invasion" can't really expect to come out with all or the bigger part of the outward thickness.
I don't know. Approaches such as the common keima kakari against hoshi often enough jump in immediately afterwards and trade influence for territory. Invasions such as in the middle of a three-space high/low extension often enough lead to taking the outside influence while letting the invaded party connect. At least those are for me prototypical examples for these words.

Come to think of it, many moves don't insist on getting what they initially seem to aim for. And these corner moves are, at least for my eyes, both an invasion and an approach (if you define an approach as »second move in the corner«).

I think what is most unclear to me is what »approach« means.
A good system naturally covers all corner cases without further effort.
dhu163
Lives in gote
Posts: 474
Joined: Tue Jan 05, 2016 6:36 am
Rank: UK 2d Dec15
GD Posts: 0
KGS: mathmo 4d
IGS: mathmo 4d
Has thanked: 62 times
Been thanked: 278 times

Re: Invasion or approach?

Post by dhu163 »

I think it approaches from inside the corner, aiming towards escaping/undercutting in two directions.

Perhaps invasion is less appropriate than usual because there are several almost even lines where W gets sente. So W is just going for life and B for solidly blocking off on the left and/or upper sides from the corner.
kyulearner
Dies in gote
Posts: 59
Joined: Fri Apr 27, 2018 11:14 pm
Rank: 4kyu
GD Posts: 0
Has thanked: 5 times
Been thanked: 18 times

Re: Invasion or approach?

Post by kyulearner »

I would say they are approaches.
1. Consideration for follow-up moves falls under the category of Joseki. There are no surrounding stones, so the value of sides, corner, influence has not shifted.
2. Calling them invasion gives a false impression that 5-4 or 3-5 gives them a corner/a stake in the corner (a stake that by attacking such "invasion", you get superior outcome) in addition to influence/side.
Post Reply