The Mad Hatter: Have I gone mad? Alice: I'm afraid so. Your'e entirely bonkers. But I'll tell you a secret. All the best people are. From the Mad Hatter's Tea Party in Alice in Wonderland by Lewis Carroll.
I've always loved this: One day Alice came to a fork in the road and saw a Cheshire cat in a tree. "Which road do I take?" she asked. "Where do you want to go?" was his response. "I don't know," Alice answered. "Then," said the cat, "It doesn't matter.