“`But I don’t want to go among mad people,’ Alice remarked. `Oh, you can’t help that, said the Cat: `we’re all mad here. I’m mad. You’re mad.’ `How do you know I’m mad?’ said Alice. `You must be,’ said the Cat, `or you wouldn’t have come here.’ Alice didn’t think that proved it at all; however, she went on `And how do you know that you’re mad?’ `To begin with,’ said the Cat, `a dog’s not mad. You grant that?’ `I suppose so,’ said Alice. `Well, then,’ the Cat went on, `you see, a dog growls when it’s angry, and wags its tail when it’s pleased. Now I growl when I’m pleased, and wag my tail when I’m angry. Therefore I’m mad.