Earlier quoted context omitted.
People don't hallucinate. That is they can pretty reliably assess if they know or don't know something.
Your comment is a perfect example of a human hallucinating something and not knowing they are wrong about it. People are confidently wrong about things _all the time_.
They might misremember, but they can know, for sure, if they have NOT come across some information. So if you ask someone if they know where `x` is, they might have came across that info, and still be wrong. But they will know if they have never come across it.
A neural network will happily produce an output when when the input is completely out of range of the training data.