“Who are you?” said the Caterpillar.

This was not an encouraging opening for a conversation. Alice replied, rather shyly, “I—I hardly know, Sir, just at present—at least I know who I was when I got up this morning, but I think I must have been changed several times since then.”

“What do you mean by that?” said the Caterpillar, sternly. “Explain yourself!”

“I can’t explain myself, I’m afraid, Sir,” said Alice, “because I am not myself, you see.”

Lewis Carroll, Alice's Adventures in Wonderland