“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 it’s tail when it’s pleased. Now I growl when I’m pleased, and wag my tail when I’m angry. Therefore I’m mad.”
“I call it purring, not growling,” said Alice.
“Call it what you like,” said the Cat.

― Lewis Carroll Tweet