I came accross the following passage in my textbook:


I can understand the meaning of the sentence, as "Due to the decrease of contents taught at school as a result of ゆとり教育, the phenomenon of children who underwent that education and don't know even things that anyone should commonly know, also happens."

Since 誰でも知っているはずのこと is the object of 知らない I would rather say directly:


Without any "で". i.e., if we were to remove the "さえ", it would apply "を":


I don't understand what is the function of で here. What am I missing?


  • 2
    They mean the same thing in this case, but でさえ sounds even more like you are incredulous about the situation to me. And if you were to replace さえ, you would use も, not を.
    – cats
    Commented Mar 29, 2021 at 20:34
  • @cats, thanks for your insight. Do you mean that 「誰でも知っているはずのことさえ知らない」 is a valid option too?
    – jarmanso7
    Commented Mar 29, 2021 at 22:58
  • @cats, why couldn't we use を? I understand that を and も add different nuances, but don't see why を wouldn't be valid. I didn't say "replace" さえ, but "remove" さえ...
    – jarmanso7
    Commented Mar 29, 2021 at 23:00
  • 3
  • 1
    @naruto I looked at those links earlier. For me, at least, they were not helpful for this question. Perhaps others are seeing something I'm missing. Commented Mar 30, 2021 at 8:27

1 Answer 1


In short, でさえ is an alternate form of さえ and means the same thing (though not interchangeable in all syntactic contexts). で here comes with さえ. で does not have its own function (e.g. locational), it simply comes attached with さえ.

Difference between さえ、でさえ explains it well enough (check links and comments).

It's acceptable to say:

  • ことさえ知らない
  • ことでさえ知らない
  • こと知らない

However, it's much, much less common to say をさえ知らない. The さえ usually replaces the を. (This is similar to how one would say リンゴが好き。ドリアンも好き。 but you wouldn't say ドリアンがも好き.)

/// If you were to completely remove でさえ, you would get:

  • ...誰でも知っているはずのこと知らない...

Which is possible, since dropping certain particles (を in this case) is possible and normal, especially in informal speech.

  • 2
    The particle も certainly replaces が. However, も does not necessarily replace を. There are numerous instances of 「をも食べる」 confirmable in online use by what appear to be native speakers: google.com/search?q=%22をも食べる%22 There are even a few (rare) cases of 「をさえも」 used all together: google.com/search?q=%22をさえも%22&tbm=bks Commented Sep 14, 2021 at 0:58
  • 1
    Thanks for the correction, I've edited it out
    – Sabrina
    Commented Sep 14, 2021 at 1:22
  • 3
    However, you cannot say をさえ知らない... I think you can. Take a look at 2.1.1.
    – Skye-AT
    Commented Sep 14, 2021 at 1:27
  • 2
    誰でも知っているはずのこと知らない ... normal -- You need を in normal speech. ここでは普通は「を」が要りますね。The post in the linked page is about dropping particles in 看板 and 標識.
    – chocolate
    Commented Sep 14, 2021 at 16:25

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .