Zokusuji
俗筋
Zokusuji literally means "crude line of play" and is often translated as "vulgar move". In Sakata Eio's Tesuji and Anti-Suji of Go, Bob Terry has translated zokusuji as anti-suji, because that seems to be the way Sakata intended it.
Sometimes the zokusuji (crude line of play) is the correct move.[1] In that case we wouldn't call it a vulgar move. Most of the time, zokusuji is incorrect, and spoils the correct line of play. In that case, we could call it anti-suji.
Although Bill has vowed not to quibble about it, we might come to a fine definition if he sheds light once more on the matter. Others literate in Japanese are most welcome too.
Bill Spight: Bob may have other reasons for his translation.
"Vulgar (line of) play" is the obvious translation and seems to fit ordinary usage, in my experience. In his book Sakata says that zokusuji involves a loss. But people will sometimes say that a play is correct, even though it is zokusuji (zokusuji nagara). Perhaps this is a case where the term has two senses.
In English, vulgar is "common" not "crude." So, when I play, my good moves are vulgar, and the rest are blunders. It could easily be common, and correct -- in fact, if the problem is easy enough for ME to read, you expect the vulgar answer to be the correct one.
If Zokusuji is like English vulgar, then there might be only one sense, If I want to avoid vulgar plays, I would never play e5. The trick is to avoid vulgar mistakes. (instinctive plays that I'd know were wrong, if I knew how to read.)
Michael Jay (new player)
An example of zokusuji, taken from Kanazawa Problem 34 / Solution.
Using the snapback suji , White lives. Later on she will be able to capture a stone at a, or Black will have to waste a move there. Capturing two stones gives her five points. This is tesuji.
This is a crude move. Yes, it's atari, and Black cannot connect at a
because he's in shortage of liberties: White will capture four stones at b. But it is still a vulgar play, and the next diagram shows why.
forces White to capture two stones in order to live. White has only four points from the capture, and she has wasted the possibility of capturing an extra stone at
, as in Diagram 1. By playing in a vulgar way, rather than tesuji, White has lost points, although the objective of living has been achieved.
Andrew Grant It's not only a matter of losing points - in Diagram 2 Black has a large ko threat left at b, whereas in Diagram 1 there is no threat.
Example 2, taken from endgame clamp:
is zokusuji. It takes gote.
plays tenuki. Later
-
is Black's sente.
is tesuji. Black sacrifices that stone for sente.
Example 3 (See Extend from a Crosscut.)
Black can play kikashi with -
, but he weakens
and leaves cutting points behind (marked). Now he can protect the cuts, but White is greatly strengthened.
Tesuji is to extend; atari atari is zokusuji.
Comment: Sometimes atari-atari is correct, zokusuji nagara. --BillSpight