I think its pretty weird to take this passage at face value. "Foucault's Pendulum" is, at least in part, about how facile this kind of yarn spinning is. Any prejudice or conclusion anyone might like to make is a few waves of the hand away from something that looks like a good argument.

Interestingly, Aristotelian physics would have described down as "the true, appropriate place" for material objects and "up" as the unnatural state, only produced by violence and bound to be corrected by the universe.

I don't remember the context in the book very well, but I remember thinking that the premise was that the speaker here (Lia) was somehow well-grounded in concrete reality, by contrast to the other super-mystical characters in the book -- that she could relate ideas to concrete human experience, while other characters were off in the proverbial cloud-cuckoo land.

Your point about Aristotle is well-taken.