Guards! Guards! (Discworld, #8)

by Terry Pratchett

Once you’ve ruled out the impossible then whatever is left, however improbable, must be the truth. The problem lay in working out what was impossible, of course. That was the trick, all right.

The reason that cliches become cliches is that they are the hammers and screwdrivers in the toolbox of communication.

People were stupid, sometimes. They thought the Library was a dangerous place because of all the magical books, which was true enough, but what made it really one of the most dangerous places there could ever be was the simple fact that it was a library.

If there was anything that depressed him more than his own cynicism, it was that quite often it still wasn’t as cynical as real life.

“Never build a dungeon you wouldn’t be happy to spend the night in yourself,” said the Patrician, laying out the food on the cloth. “The world would be a happier place if more people remembered that.”

Never trust any ruler who puts his faith in tunnels and bunkers and escape routes. The chances are that his heart isn’t in the job.”

“I believe you find life such a problem because you think there are the good people and the bad people,” said the man. “You’re wrong, of course. There are, always and only, the bad people, but some of them are on opposite sides.”

They accept evil not because they say yes, but because they don’t say no.