Discworld – Small Gods (Terry Pratchett)

"You call this philosophy?" roared Didactylos, waving his stick.

Urn cleaned pieces of the sand mold from the lever.

"Well … natural philosophy," he said.

The stick whanged down on the Moving Turtle's flanks.

"I never taught you this sort of thing!" shouted the philosopher. "Philosophy is supposed to make life better! "

"This will make it better for a lot of people," said Urn, calmly. "It will help overthrow a tyrant."

"And then?" said Didactylos.

"And then what?"

"And then you'll take it to bits, will you?" said the old man. "Smash it up? Take the wheels off? Get rid of all those spikes? Burn the plans? Yes? When it's served its purpose, yes?"

"Well- Urn began.

"Aha!"

"Aha what? What if we do keep it? It'll be a … a deterrent to other tyrants!"

"You think tyrants won't build 'em too?"

"Well … I can build bigger ones!" Urn shouted.

Didactylos sagged. "Yes," he said. "No doubt you can. So that's all right, then. My word. And to think I was worrying. And now … I think I'll go and have a rest somewhere …

He looked hunched up, and suddenly old.

"Master?" said Urn.

"Don't `master' me," said Didactylos, feeling his way along the barn walls to the door. "I can see you know every bloody thing there is to know about human nature now. Hah!"