In a conversation in 1971 with John Gerassi, a political science professor at Queens College in New York, Jean-Paul Sartre recalled an experience with drugs in 1929 while attending the École Normale Supérieure.

Sartre: Yeah, after I took mescaline, I started seeing crabs around me all the time. They followed me in the streets, into class. I got used to them. I would wake up in the morning and say, “Good morning, my little ones, how did you sleep?” I would talk to them all the time. I would say, “O.K., guys, we’re going into class now, so we have to be still and quiet,” and they would be there, around my desk, absolutely still, until the bell rang.

Via NYT (here)