`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.´

`I call it purring, not growling,´ said Alice.

`Call it what you like,´ said the Cat.