The Extreme Example
さえ picks the most surprising member of a group to make a point about all of them.
- 子供さえ知っている。(Even a child knows that.)
The logic is: if it's true of this one, it's true of everyone.
Against も
も also means "even", and さえ is stronger:
| Pattern | Force |
|---|---|
| 子供も知っている | children know it too |
| 子供さえ知っている | even a child knows it — so you certainly should |
さえ implies a scale and puts the subject at the unexpected end of it.
With a Negative
The negative is where さえ is most common, meaning "not even":
- 名前さえ知らない。(I don't even know his name.)
Particles Before さえ
は and が drop; other particles stay and さえ follows them:
| 水さえ飲めない | を drops |
| 親にさえ言えない | に stays |
でさえ is a common emphatic variant: 大人でさえ難しい.