When to use ～ので vs ～から

Question

I was looking in A Dictionary of Basic Japanese Grammar when I saw something on page 329 which truly shocked me:

"node cannot be used and kara must be used [... when ...] the main clause is a command, request, suggestion or invitation"

×　この映画はためになるので行きなさい
○　この映画はためになるから行きなさい

×　あしたのショーはおもしろいのでぜひ見に来て下さい
○　あしたのショーはおもしろいからぜひ見に来て下さい

×　この本はとてもおもしろいのでみんなも読んだほうがいいよ
○　この本はとてもおもしろいからみんなも読んだほうがいいよ

×　いい酒をもらったので一緒に飲みましょうか
○　いい酒をもらったから一緒に飲みましょうか

I do not consider the × sentences ungrammatical at all!

I, on the other hand, consider ので more polite than から, and would hesitate to use から in 丁寧語 sentences (except where only から is an option, e.g. からです, でしょうから). So I actually prefer the × sentences in the second and fourth examples.

What is going on? Is the dictionary wrong, am I wrong, or has the distinction between the two particles shifted in nuance? (The dictionary was written in 1986).

Answer 1

I did not know that claim and I do not agree to it, but judging from several web pages I found from search, it seems that the difference between から and ので has been one of the most controversial topics in Japanese linguistics. The usage may have changed over time, but it was controversial even at the time of the publication of the book from which you quoted the claim.

The explanation which you quoted is based on the theory by Masaru Nagano (永野賢) in 「から」と「ので」とはどう違うか (1952). According to his theory, から explains a subjective reason whereas ので describes a cause-result relationship in an objective manner, and because of this difference, ので cannot be used to state a reason for a request.

However, Nagano admits that ので is sometimes used to state a reason for a request when the sentence is in the polite form. He explains it as follows: because から describes a subjective reason, it can make the sentence sound more strongly opinionated. Using ので instead softens the expression. According to Nagano, using ので to state a reason for a request in a non-polite sentence is ungrammatical.

Not everyone agrees on this explanation. For example, Tsutomu Miura (三浦つとむ) claims that it is nonsense in 日本語の文法 (1975).

Answer 2

In ordinary life, people may use both types of sentences, as you wrote. But there is a subtle difference, and using ので here is wrong if you are strict. The book well describes this point, and so is a good book.

ので connects a cause-effect relation, and probably, it does not prefer a logically narrower scope than the inflection or the compounded part of the verb. And if the scope of it is not a proposition but is a command, request, suggestion, or invitation, it will not make sense semantically.

あしたのショーはおもしろいので[ぜひ見に来て下さい]
a. 'As for tomorrow's show, [please come to see it] because it is interesting.'

Here, ぜひ見に来て下さい or please come to see it is a request, and does not have a truth value like a proposition. You cannot say that it is true or false because of another fact. In order for it to make sense, the logical connection has to be done in a position lower than the request:

b. 'As for tomorrow's show, please [come to see it because it is interesting].'

come to see it is a proposition that will reveal its truth value when the time comes (tomorrow), and there is nothing wrong with it having a cause/motivation because it is interesting. ので seems to only allow interpretation a., not b. That is the reason you cannot use it.

On the other hand, with から, expresses motivation, and as you can tell from its form, it is just a postposition phrase, and can take scope within the verb phrase.

あしたのショーは[おもしろいからぜひ見に来て]下さい

It allows the interpretation b., so that is why you can use it.