Psychedelic therapy, naive reckless pursuers of cosmic insight, more likely. Terence McKenna apparently had such an experience. Only if you pay attention to actually what he said. It comes across as so much incoherent pseudo profound glossolalia word salad. There's a distinct feeling of déjà vu about this :)
“The Electric Kool-Aid Acid Test” https://en.wikipedia.org/wiki/The_Electric_Kool-Aid_Acid_Tes...