And then there were cats, thought Dog. He'd surprised the huge ginger cat from next door and had attempted to reduce it to cowering jelly by means of the usual glowing stare and deep-throated growl, which had always worked on the damned in the past. This time they had earned him a whack on the nose that had made his eyes water. Cats, Dog considered, were clearly a lot tougher than lost souls. He was looking forward to a further cat experiment, which he planned would consist of jumping around and yapping excitedly at it. It was a long shot, but it just might work.

When it's time to stop living, I will certainly make Death my number one choice!

The theater troubled her. It had a magic of its own, one that didn’t belong to her, one that wasn’t in her control. It changed the world, and said things were otherwise than they were. And it was worse than that. It was magic that didn’t belong to magical people. It was commanded by ordinary people, who didn’t know the rules. They altered the world because it sounded better.

... when your name is really and truly Percy Blakeney, pronounced 'Black-knee', and you still have bad acne in your twenties, you accept Pimple as a nickname and are grateful that it wasn't anything worse.

I would like permission to fetch a note from my mother, sir' Ridcully sighed. 'Rincewind, you once informed me, to my everlasting puzzlement, that you never knew your mother because she ran away before you were born. Distinctly remember writing it down in my diary. Would you like another try?' 'Permission to go and find my mother?'

But of course, what the eagle does not realize is that it is participating in a very crude form of natural selection.One day a tortoise will learn how to fly.

Perhaps it would be simpler if you just did what you're told and didn't try to understand things.