1865 Alice's Adventures in Wonderland 

For, you see, so many out-of-the-way things had happened lately, that Alice had begun to think that very few things were really impossible.

-I can't explain myself I'm afraid, sir because I'm not myself, you see

-How do you know I'm mad? 'You must be', said the Cat, 'or you wouldn't have come here'

- I know who I was when I got up this morning 
but I think I must have been changed several times since then