- (idiomatic) Mentally competent; not absent-minded or insane.
- Is he all there?
- I don't think he's all there...
- I think he's not all there...
1885, Amelia E. Barr, chapter 1, in Jan Vedder's Wife:
- A suspicion that “he was not all there,” and therefore “one of God’s bairns,” had insured him, during his long orphanage, the food, and clothes, and shelter, necessary for life; but no one had given him love.
- 1922, James Joyce, Ulysses, Episode 15:
- His submission is that he is of Mongolian extraction and irresponsible for his actions. Not all there, in fact.
- 2011, Julie Keith, The Devil Out There, ISBN 9780307369710, Part 1 (Google preview):
- [S]he smiled at me in a such a silly way, I thought to wonder if she was all there.
- Used other than with a figurative or idiomatic meaning: see all, there.
- Often used in the negative construction, "not all there", to mean mentally incompetent, of low intelligence, or absent-minded.
negative form, "not all there": mentally incompetent