“As humans, we have invented lots of useful kinds of lie. As well as lies-to-children ('as much as they can understand') there are lies-to-bosses ('as much as they need to know') lies-to-patients ('they won't worry about what they don't know') and, for all sorts of reasons, lies-to-ourselves. Lies-to-children is simply a prevalent and necessary kind of lie. Universities are very familiar with bright, qualified school-leavers who arrive and then go into shock on finding that biology or physics isn't quite what they've been taught so far. 'Yes, but you needed to understand that,' they are told, 'so that now we can tell you why it isn't exactly true.' Discworld teachers know this, and use it to demonstrate why universities are truly storehouses of knowledge: students arrive from school confident that they know very nearly everything, and they leave years later certain that they know practically nothing. Where did the knowledge go in the meantime? Into the university, of course, where it is carefully dried and stored.”

“Mind you,” said Ponder, “the universe does have a rhythm. Day and night, light and dark, life and death—” “Chicken soup and croutons,” said Ridcully. "Well, not evert metaphor bears close examination".”

“Cats do not hunt seals. They would hunt them if they knew what seals and where to find them. But they do not know, so it's okay.”

“Humans need fantasy to be human.”

“NEITHER RAIN NOR SNOW NOR GLOM OF NIT CAN STAY THESE MESENGERS ABOT THEIR DUTY”

“It's rude to stare," said the troll. Its mouth opened with a little crest of foam, and shut again in exactly the same way that water closes over a stone. "Is it? Why?" asked Rincewind. How does he hold himself together, his mind screamed at him. Why doesn't he spill?”

“I HAVE MADE THIS FOR YOU. She reached out and took a damp square of cardboard. Water dripped off the bottom. Somewhere in the middle, a few brown feathers seemed to have been glued on. 'Thank you. Er ... what is it?'ALBERT SAID THERE OUGHT TO BE SNOW ON IT, BUT IT APPEARS TO HAVE MELTED, said Death. IT IS, OF COURSE, A HOGSWATCH CARD.'Oh ...' THERE SHOULD HAVE BEEN A ROBIN ON IT AS WELL, BUT I HAD CONSIDERABLE DIFFICULTY IN GETTING IT TO STAY ON. 'Ah...'IT WAS NOT AT ALL COOPERATIVE.'Really ...?'IT DID NOT SEEM TO GET INTO THE HOGSWATCH SPIRIT AT ALL.”

“Why are our people going out there,” said Mr. Boggis of the Thieves’ Guild."Because they are showing a brisk pioneering spirit and seeking wealth and … additional wealth in a new land,” said Lord Vetinari.“What’s in it for the Klatchians?” said Lord Downey.“Oh, they’ve gone out there because they are a bunch of unprincipled opportunists always ready to grab something for northern,” said Lord Vetinari.“A mastery summation, if I may say so, my lord,” said Mr. Burleigh. The Patrician looked down again at his notes. “Oh, I do beg your pardon, I seem to have read those last to sentences in the wrong order…”

“Susan hated Literature. She'd much prefer to read a good book.”

“The trouble is you can shut your eyes but you can’t shut your mind.”

“Then Tak looked upon the stone and it was trying to come alive, and Tak smiled, and wrote All things strive.And for the service the stone had given, he fashioned it into the first Troll, and delighted in the life that came unbidden.”