Philip Pullman, The Golden Compass

"All good things pass away."

"One moment several things are possible, the next moment only one happens, and the rest don't exist. Except that other worlds have sprung into being, on which the did happen."

"That’s the duty of the old, to be anxious on behalf of the young. And the duty of the young is to scorn the anxiety of the old."

"You cannot change what you are, only what you do."