http://jisho.org/search/%E7%9B%B8%E5%A0%B4

A second sense of the word is speculation, which seems more likely, a third meaning is listed as estimation.

So it probably means, the sequence up to Black 13 is put forward as a likely outcome. The nuance being that it is not being put forward as the best play, or the most correct play, but as a play which is OK. It might well be the best play but the Japanese language has a tendency to be humble when make assertations, rather than saying, the sequence until Black 13 is correct, or right, it is saying the sequence until Black 13 shows possible play.

I don't speak Japanese, but I seem to recall John Fairbairn using the phrase "market price" in his books. Until he comes along to elucidate, I think it often refers to getting a known reasonable benefit from the position. Like aiichigo said maybe not the totally optimal, but good enough. I think there is an element of cashing in your aji: maybe you could get more later, but maybe you could get less so you go for the clear reasonable benefit now.

There's some discussion on it over at SL: http://senseis.xmp.net/?Souba

This is actually a slightly strange discussion. Why would we expect Japanese to be unlike other human languages in that the meaning of words depends to a certain extent on the context. Dictionary definitions are generally in order of frequency of use, but of course that can be the result of the frequencies of the contexts in discourse or print.

So this term means "market price" when used in the context of the world of commerce perhaps including daily shopping stuff. Surely that would be a more common context than playing go.

The question maybe should be "what does this term mean when talking about go?" not even referring to the dictionary definition at all.

I mean after all, if we were looking at a dictionary of English, would we expect to find even among the rarer uses of "eye" how we use this word in go?

In the context of goods, such as stocks, that are sold in a market, 相場 would be used for the market price. It would be the price that is fair for both seller and buyer. In the context of the game go when a position is given there are many possible ways to play. If a sequence has both players making good (or best) moves the result could be called soba (相場). I can imagine someone asking a pro "What would happen if Black played this move?". The pro might show a sequence of a few moves and saying "Here is how it might reasonably go". The idea is that both sides do well as possible.

Yes of course, the real question was "what does this term mean in the context of go?" The strangeness to which I was referring was bringing in the dictionary meaning "market price", "price fair to buyer and seller".

There of course might be a connection between that meaning and the meaning of the term in the context of go. But no particular reason to suppose that there would be.

Try the English terms eye and ladder. Would you expect any of the meanings given in a dictionary to help us understand their meaning within the context of go?

On the contrary, it would be quite odd indeed if there isn't.Yes. With elaboration.

In an alternate universe where the Go terms for 'eye' and 'ladder' are instead 'red' and 'green', it would take a little more explanation.

Not really on topic, but when a Japanese pro was visiting the Seattle Go Center awhile back, he told me that go was a game of "kakehiki".

This word can be used to mean bargaining/haggling.

Perhaps when two players face one another on the go board and bargain/haggle one another, "souba" is what happens when they reach a fair agreement

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(kind of off topic, about the origin)

We Japanese do not use *this* 相場 in our natural conversation.
It's a go-specific usage. At first, I thought a word 相場 was invented
in the Meiji period (next to the Edo period) to translate Das Kapital
or something. A lot of Japanese words were born in the period.
In addition, 相場 sounds like one of imported words such as 電場 (electric field).

But it seems not. This blog post says this word may be 500 years old.
Maybe not. Even we Japanese don't know when the word was born.

Update:


Yes, it is.