ではないか and のではないか
ではないか and のではないか are extremely similar, but have different meanings.
ではないか – Isn’t it,,,? (I disagree, I think its something else)
のではないか – I think its…Isn’t it? (A way to soften your viewpoint).
These words are mostly written, common in academic papers, etc.
For the spoken version, see じゃないか
These patterns may also appear as ではないか、ではないでしょうか、and ではないですか。
In the future, I will likely create another page or combine this into a different page covering all of the usages of ではないか and some extra details, but for now, we’re only going to deal with this one specific issue.
If you can read Japanese and want more detailed information, here is a 22 page academic paper.
ではないか
Isn’t it…? (Disagreement)
Verb/い Adjective + ではないか
Noun/な Adjective + ではないか
Noun/な Adjective + なのではないか (Annoying)
This is the written form of tag question じゃないか.
It expresses disagreement, and doesn’t try to hide it.
Although it’s “isn’t it”, it really comes across more like “it is”.
This pattern is less likely to be asking for confirmation.
Examples
- おくれるではないか
We are going to be late aren’t we.
- クマではないか
Oh its a bear. - 優しい方ではないか
Isn’t he nice.
のではないか
I think its….isn’t it (Soft statement)
Verb/い Adjective + のではないか
Noun/な Adjective + なのではないか
のではないか is ではないか but with added uncertainty.
This is mostly used to soften an opinion by phrasing it in less sure terms.
This pattern may “ask” for confirmation.
However, it is not appropriate in cases where there is no uncertainty.
Examples
- 彼も行くのではないでしょうか
I think he’s going to go right? - このままだと遅れるのではないでしょうか
At this rate we’re going to be late right? (I think). - 嘘なのではないか
I think that’s a lie right. - 間に合わないのではないでしょうか
I think we aren’t going to make it.
Nouns and なのではないか
You probably noticed that Nouns and な Adjectives can become なのではないか for both ではないか andのではないか.
This is annoying and means you need to use context to figure out whether the other person meant to add uncertainty or not (and thereby soften their opinion).
Non-Interchangeable Cases
There are some cases where these are not interchangeable, mostly cases where there is no uncertainty。
Take this example from Stack Exchange:
その日、私はホームに入ってきた電車に飛び乗った。ところが、電車は反対方向に走り始めた（ ）。
私は電車の行き先を確かめなかったことを後悔した。
１．ではない
２．ではないか
３．のではない
４．のではないか
Check out the link for the correct answer and an explanation.