Equal Rites (1987)

They both savoured the strange warm glow of being much more ignorant than ordinary people, who were only ignorant of ordinary things.

For animals, the entire universe has been neatly divided into things to (a) mate with, (b) eat, (c) run away from, and (d) rocks.

Esk, of course had not been trained, and it is well known that a vital ingredient of success is not knowing that what you are attempting can't be done. A person ignorant of the possibility of failure can be a half-brick in the path of the bicycle of history.

... she was already learning that if you ignore the rules people will, half the time, quietly rewrite them so that they don't apply to you.

It has already been revealed that light on the Discworld travels slowly, the result of its passage through the Disc’s vast and ancient magical field.
So dawn isn’t the sudden affair that it is on other worlds. The new day doesn’t erupt, it sort of sloshes gently across the sleeping landscape in the same way that the tide sneaks in across the beach, melting the sand castles of the night. It tends to flow around mountains. If the trees are close together it comes out of woods cut to ribbons and sliced with shadows.