Terence McKenna on Serotonin and DMT

Terence Kemp McKenna (November 16, 1946 – April 3, 2000) was an American ethnobotanist and mystic who advocated the responsible use of naturally occurring psychedelic plants. He spoke and wrote about a variety of subjects, including psychedelic drugs, plant-based entheogens, shamanism, metaphysics, alchemy, language, philosophy, culture, technology, ethnomycology, environmentalism, and the theoretical origins of human consciousness.