Philosophers' Convention

There is a huge philosophers' convention at the local hotel, and all the great philosophers are there.
Pascal is one of the last ones to arrive, and at the front desk he is told that his reservation was lost, and there are no more rooms at the hotel.
"This is preposterous!" he exclaims. "Where can I spend the night, the entire town has no vacancies!"
The desk clerk tells him that he may try to find one of his philosopher friends to share a room with him.
So he knocks on the first door, and Plato opens it. Pascal explains his problem, but Plato is already sharing his room with Satre, and that's depressing enough.
So Pascal tries the next room. Descartes opens the door. He has had a long day, and is in a bit of a bad mood. Pascal asks to share the room.
Descartes replies haughtily, "Share my room?!? I think NOT!"
And instantly he disappears in a cloud of smoke.