Cogito Ergo Sum

Rene Descartes was at a cocktail party one evening when an attendant approached him and asked if he'd like a drink.

Mssr. Descartes thought for a moment...

and said, I think not.

And he disappeared.

If you don't get the joke, click here.

I Forgot to mention: Amalthea told me that joke when she was 11 years old.