If a coin comes down heads, that means that the possibility of its coming down tails has collapsed. Until that moment the two possibilities were equal. But on another world, it does come down tails. And when that happens, the two worlds split apart.

All writing is difficult. The most you can hope for is a day when it goes reasonably easily. Plumbers don't get plumber's block, and doctors don't get doctor's block; why should writers be the only profession that gives a special name to the difficulty of working, and then expects sympathy for it?

This is the value for me of writing books that children read. Children aren't interested in your appalling self-consciousness. They want to know what happens next. They force you to tell a story.

The range of individuality in children is infinite, but every class of children seemed to have the same groups. And there was a chief girl and a chief boy - a girl that all the other girls of that age looked up to and imitated and a boy that all the boys looked up to and imitated. I realized that if I got them on my side and exclusively taught them for a couple of weeks, maybe for the first full term, then I wouldn't have any trouble. Teachers often make the mistake of thinking they're the boss of the class; they're not. The boss of the class is sitting down there somewhere.

People are too complicated to have simple labels.

Iorek Byrnison: Can is not the same as must. Lyra Silvertongue: But if you must and you can, then there's no excuse.

If there is a war to be fought, we don’t consider cost one of the factors in deciding whether or not to fight.