I heard a joke today that I thought was hilarious. I modified it (like a nerd) and added the appropriate philosophies for Aristotle and Plato.

Aristotle, Plato, and Descartes were taking a plane to a philosophy convention, and a flight attendant came to see if they'd like anything to drink. Aristotle said that he'd like a Coke, and he promptly drank it, saying that being consumed was the proper function of a virtuous drink. Plato asked for tomato juice and then dumped it on the ground, exclaiming that the material form of the juice was only a shadow of true juice and, thus, couldn't be experienced in its fullest form anyway. Immersed in thought, Descartes didn't say anything until the attendant asked him whether he wanted something to drink. Descartes responded, "I don't think so.", and he disappeared.

Click here if you didn't get the punchline.