"Who are you?" asked the caterpillar.
Alice answered a little sheepishly, "Sir, I - I don't know yet, at least when I woke up this morning, I still knew who I was, but after that I've changed so many times."
The caterpillar said coldly, "What do you mean? Explain yourself!"
"Sir, I'm afraid I can't explain, because I'm not myself," said Alice.
from Alice's Adventures in Wonderland by Lewis Carroll