The short conversation that follows eventually led to a tree religion. Its tenet of faith was this: a tree that was a good tree and led a clean decent and upstanding life could be assured of a future life after death. If it was very good indeed it would eventually be reincarnated as five thousand rolls of lavatory paper.

It doesn't matter if dragons are flying overhead or whatever - a lot of Victoriana is still cut in the frame of fantasy.

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.

It is often said that before you die your life passes before your eyes. It is in fact true. It's called living.

Sometimes I think a man could wander across the disc all his life and not see everything there is to see,' said Twoflower. 'And now it seems there are lots of other worlds as well. When I think I might die without seeing a hundredth of all there is to see it makes me feel,' he paused, then added, 'well, humble, I suppose. And very angry, of course.

Vimes struggled to his feet, shook his head and set off after it. No thought was involved. It is the ancient instinct of terriers and policemen to chase anything that runs away.

Botswana is also the only country in the world with a colour in its flag meant to represent rain (a sort of blue-grey). Not many people know this.