Some people believe that when you die, you cross the River of Death and have to pay the ferryman. People don’t seem to worry about that these days. Perhaps there’s a bridge now.

However, you do need rules. Driving on the left (or the right or, in parts of Europe, on the left and the right as the mood takes you) is a rule which works, since following it means you're more likely to reach your intended rather than your final destination.

His mind worked fast, flying in emergency supplies of common sense, as human minds do, to construct a huge anchor in sanity and prove that what happened hadn't really happened and, if it had happened, hadn't happened much.

Plot exposition that can be gently wound out by the authorial voice and internal monologue of a character in the length of a page has to be delivered in a matter of seconds on the stage.

What was the point of education, he thought, if people went out afterward and used it?

Never build a dungeon you wouldn't be happy to spend the night in yourself. The world would be a happier place if more people remembered that.

I get it,' said the prisoner. 'Good Cop, Bad Cop, eh?' If you like.' said Vimes. 'But we're a bit short staffed here, so if I give you a cigarette would you mind kicking yourself in the teeth?