Having trouble parsing this triple negative sentence

Question

In my JLPT practise book, there is this sentence, which is designed to test if one can track all the negations:

その仕事{しごと}ほどおもしろくない仕事{しごと}はないのではないかと、私{わたし}は思{おも}った。

Up to の, I think it's saying, "there is no job as uninteresting as that job." But then we hit のではない, and I get a bit lost. I feel like it's saying "there is no job where there is no job as boring as that job," which doesn't really make sense.

How do I parse this sentence so that I can understand whether the speaker thinks その仕事{しごと} is interesting or uninteresting?

Answer 1

How about parsing it as this:

「『その仕事ほどおもしろくない仕事はない』のではないか？」と、私は思った。

... reading ～～のではないか？ as a rhetorical question.

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You can say 「～(の)ではないかと思う」(or more colloquially ～～(ん)じゃないかと思う) to mean "I suspect that~~" or "I think it probably is~~".

Answer 2

He thinks that "that job" is very uninteresting.

I'm sorry I can't split this grammatically, but 「～のではないか」 corresponds to "I wonder whether ～～", where ～～ is something (often bad) which can actually happen.

You can see many examples here.

その仕事ほどおもしろくない仕事はないのではないかと、私は思った。
"I'm afraid that there is no job as uninteresting as this," I thought.

Answer 3

その[仕事]{しごと}ほどおもしろくない[仕事]{しごと}

A job as boring as that one

はない

Does not exist. There is not such a job.

のではないかと、[私]{わたし}は[思]{おも}った。

のではない or んじゃない + か being a rhetorical question marker, a supposition, a "wondering if."

So basically you get something like "I wondered if there's a job as boring as that one."