This post is going to be incredibly long. So please ignore it if you want to. I could be totally wrong anyway.
I read through the English version of the article by Kuno published in 1973, which Jarvik7 kindly gave the link to. I also ran my eye over thorough explanations of は/が found in 現代日本語文法概説, which is based on recent results in linguistics.
Now that I have read through them, it's not surprising to me any more that Kuno's research method is found almost exclusively in the study of difference between English and Japanese these days. I feel sorry for perplexed learners who had to use textbooks that based on his view to learn は/が. Their textbooks are simply wrong. I'm under the impression that their teachers didn't know what they were talking about.
First of all, it seems the consensus among researchers today is that something wasn't quite right about Kuno's view of は/が. According to 現代日本語文法概説, you can read about how Kuno got tripped up in specialist works in academia such as 「助詞の意味と機能について−「は」と「が」を中心に−」 by 柴谷方良 written in 1995. The author is (was?) the dean of the Department of Linguistics at Rice University if you doubt the credibility, though I don't think "who" should make any difference. In 現代日本語文法概説, there is a direct quote in which 柴谷方良 is talking about Kuno's errors.
Anyway, one of the major errors Kuno made was about sentences such as 大勢の人はパーティーに来ました。, which Jarvik7 and I have discussed. This sentence is considered grammatical in recent books including 柴谷方良's work while it is ungrammatical in Kuno's view. What he was saying about the sentence was like "'
You are a student' is ungrammatical in English because the literal translation of the verb '
are' in another language X is considered the plural of '
be.' You could say it's grammatical only when context says you can see it as a special singular '
are.' However, '
You are a student' is ungrammatical without context."
In the English article he first explores how native English speakers compose English sentences (He spent the whole 5 pages...) and then tries to explain the Japanese language from the viewpoint of the English language. He defines "themes," which roughly explain how a native English speaker's mind works, and then classifies は according to the English themes. And he claims a Japanese sentence using は is ungrammatical when his version of literal translation into English doesn't much up with the English theme which he thought the translation should have fallen into. But obviously his definition of "ungrammatical" doesn't resonate with native Japanese speakers' intuitions. There are lots of examples he claims to be ungrammatical but native speakers would think natural. So he makes up a special term "contrastive usage" and says it's not ungrammatical when you see it as contrastive は. Of course, this view is considered nonsense by today's researchers.
I could be completely wrong because I'm not used to reading this kind of thing in English. But one thing I am certain is that his work shouldn't be recommended to learners of contemporary Japanese. In page 42 there is an example sentence that is considered a faux pas by the standards of today. It contains a very controversial word that my IME (I'm using ATOK) forbids to write in kanji. I'm guessing choosing the sentence as an example was all right back then. Also, there are a few example sentences that don't sound natural to my ears, though it may be typos; there are a few obvious typos in his illustrative sentences.
Anyway, here are
explanations of は/が posted on the forum of Tae Kim's Guide by the author of 現代日本語文法概説. He explains the particles by showing how/why/where popular explanations such as topic vs. subject and new vs. old are wrong. His explanation is based on very recent research in contemporary Japanese. Since the posts are very long and in Japanese, they wouldn't be helpful to beginners. But it might be interesting if you're advanced learners having trouble understanding は and が.
He concludes that the wrong explanations are ok as long as learners can understand proper usage. I'm not sure if he's too optimistic, but it sure doesn't seem like linguistically proper explanations help beginners. It might be better to listen to whichever explanation you think makes sense and forget about it as soon as possible.
Edited: 2009-06-11, 2:06 am