It is a special kind of enlightenment to have this feeling that the usual, the way things normally are, is odd--uncanny and highly improbable. G. K. Chesterton once said that it is one thing to be amazed at a gorgon or a griffin, creatures which do not exist; but it is quite another and much higher thing to be amazed at a rhinoceros or a giraffe, creatures which do exist and look as if they don't.