Psilocybin

One study...found that the psilocybin experience also had a positive and lasting effect on the personality of most participants. This is a striking result, since the conventional wisdom in psychology holds that personality is usually fixed by age thirty and thereafter is unlikely to substantially change. But more than a year after their psilocybin sessions volunteers who had had the most complete mystical experiences showed significant increases in their “openness,” one of the five domains that psychologists look at in assessing personality traits. (The others are conscientiousness, extroversion, agreeableness, and neuroticism.) Openness, which encompasses aesthetic appreciation, imagination, and tolerance of others’ viewpoints, is a good predictor of creativity.

— from The Trip Treatment by Michael Pollan

Image: Kairouan (III) by August Macke (1914)