Questions about the construction A が B(B is a noun)+のだ/のである?

Question

「……そんな危険な大学出身者どもを、ありがたく受け入れるのが塾講師業界ってんだから」

Hi. The speaker is a 塾講師 and he is talking with a stranger in a bar.

Hi. I have some problems with the bold part. I know it equals 業界というのだから. But I’m not sure if the という is 伝聞 here.

1. Grammatically speaking, can we insert a だ between 業界 and って? And can we say 業界なのだから here?
2. If we can, are the three versions (業界だってんだから、業界なのだから、業界ってんだから) the same in meaning and nuance?

A previous related thread addressed the pattern というのだから, where という was interpreted as “they say”. But as far as I know, there are many cases where the という in というのだから is just for emphasis without having a concrete meaning. https://japanese.stackexchange.com/questions/11046/what-are-the-usages-of-のだから

I ask this question because the topic sentence reminds me of another sentence that I have come across before. Here goes it,

だがそれも無理からぬことなのかもしれない。 ただでさえ、女子の手作りクッキーをいただくなんてのは、他の男子たちの嫉妬の的だ。 しかもそれが、転入直後から、彼女にしたい女子ランキングを駆け上がった(と噂の)あの夜刀神十香のものだというのである。

The context is that the girl 十香 made some cookies for the protagonist, of whom the other boys were envious.

I was told the という in the bold part above meant “they say” but now that I read it again, I think the という could also just be an emphasis without any meaning. And unlike the first example, there is a だ between もの and という.

So let me summarize my question.

If the construction is A が B(B is a noun)+のだ/のである, as in the two sample sentences, when is a だ immediately after B necessary and when is the だ optional?

When is a って/という immediately before のだ/のである necessary? If the って/という is unnecessary, なのだ works as well in the construction, I think.

Thank you.

Answer 1

The most complete form is 塾講師業界だというのだから, which can be contracted to 塾講師業界だってんだから, which in turn can be further contracted to 塾講師業界ってんだから.

The result of “reverse transformation” from the last one, 塾講師業界というのだから, is also good, although I personally feel something is missing in it. (This is precisely the reason I see 塾講師業界ってんだから more as a second-level contraction of 塾講師業界だというのだから than as a first-level contraction of 塾講師業界というのだから, at least in this context.)

という in 塾講師業界だというのだから carries a sense of unexpectedness or surprise, as suggested in one of the answers to the earlier question. It’s like saying “the industry that willingly accepts such rogue graduates is, of all industries, the cram school industry.”

I think the reason 塾講師業界だというのだから sounds more natural (at least to me) than 塾講師業界というのだから is that the final だ or である is essential in stating the fact whose unexpectedness is to be emphasized: そんな危険な大学出身者どもを、ありがたく受け入れるのが塾講師業界だ.

Given enough context, 塾講師業界なのだから could also be interpreted the same way, but it’s quite ambiguous as it can be easily interpreted as saying “since it’s the cram school industry that …,” which sounds neutral and lacks emphasis.

という in あの夜刀神十香のものだというのである can also be understood the same way. The character received the cookies from, of all girls in the school, that Yatogami Toka.

あの夜刀神十香のものというのである, without だ, sounds even less natural than 塾講師業界というのだから. I think this is because 「〜が塾講師業界」 could still be interpreted as something people are saying, permitting という to immediately follow it, whereas this possibility is ruled out with あの夜刀神十香のもの, which is a known fact for the narrator, not hearsay.

Still, the contracted あの夜刀神十香のものってんだ sounds acceptable in casual speech. I would suppose the speaker to be an 江戸っ子, though.

Answer 2

small "つ"

If we can, are the three versions (業界だってんだから、業界なのだから、業界ってんだから) the same in meaning and nuance?

In this case, a small "つ" is very Spoken language. You won't see a small "つ" in usage like this one in a serious written sentence. In fact, the sentence you illustrated is also a situation where people are talking.

At least, as a Japanese, my guess is that 「そんな危険な大学出身者どもを、ありがたく受け入れるのが塾講師業界ってんだから」 is a middle-aged man talking.

As a Japanese person, when I'm reading a novel, I can judge who is speaking by looking at "how they are talking"(Of course, I don't always know.).

You write that they are talking in a bar, which is exactly the spoken language that was in the bar.

業界だってんだから vs 業界ってんだから

業界だってんだから and 業界ってんだから are similar, but to explain, 業界だってんだから is more of an expression that emphasizes the word "業界".

という（ってん）

ありがたく受け入れるのが塾講師業界ってんだから

In this case, "という（ってん）" is not that they said so. This meaning indicates that it is commonly referred to as such.

（英語が下手なので、日本語で説明すると「一般的にそう言われている」という意味で使われています。少なくとも「塾業界」ではそう言われていると読み取れます）

あの夜刀神十香のものだというのである

In this case, the sentence seems to be valid without the "という".

In other words, "あの夜刀神十香のものである" is OK.

I don't know the grammatical usage. But from the mood of the text, it feels more natural to have an "という".

If you leave out the "という", you can also change the previous sentence to make it more natural.

だがそれも無理からぬことだ。 
（略）
あの夜刀神十香のものである。

（つまり作者が断定を避けて表現したいか、断定して表現したいかの違いだと考えます。もとものの文は「らしい」や「という」を使って、ぼかした表現となっていますが、このような小説?では自然に使われる表現と思います。）