THC (tetrahydrocannabinol) and psychedelics like psilocybin, LSD, and mescaline have been used for millennia. Evidence includes cave paintings in Algeria (4700 BCE) depicting mushroom use, and Mesoamerican stone figures with mushrooms growing from heads. Ancient cultures used these substances for healing, divination, and spiritual connection.
Explore more: Plant Medicine & Psychedelics Throughout History
From the 1960s counterculture to modern wellness movements, psychedelics have shaped art, music, and social movements. Cannabis has similarly evolved from taboo to mainstream, influencing fashion, film, and lifestyle branding.
Harvard’s interdisciplinary study explores these cultural intersections: Harvard Study of Psychedelics in Society and Culture
Both THC and psychedelics were classified as Schedule I substances under the Controlled Substances Act of 1970. Since 2000, cannabis legalization has expanded across U.S. states, and psychedelics have seen decriminalization in cities like Denver (2019). Legal reform is increasingly framed as a matter of cognitive liberty and neurodiversity.
Read legal analysis: Psychedelic Law Reform and Neurodiversity
THC is used for pain relief, nausea, and appetite stimulation. Psychedelics are being studied for depression, PTSD, addiction, and existential distress. Ketamine and esketamine are FDA-approved for treatment-resistant depression, with effects resembling classic psychedelics.
Harvard’s PULSE project explores medical and spiritual intersections: PULSE Initiative
Indigenous cultures have long used plant medicines in ceremonial contexts. The Mazatec people of Mexico use psilocybin mushrooms in healing rituals. Native American Church members use peyote in religious ceremonies protected under U.S. law.
Learn from Mazatec educator Elías García Méndez: Casa Adobe Reflections
Psychedelics have been linked to mystical experiences, spiritual awakenings, and esoteric practices. The Eleusinian Mysteries of ancient Greece may have involved psychedelic kykeon. Modern occultists and psychonauts explore altered states for insight and transformation.
Explore spiritual intersections: Psychedelics and Spirituality
See Harvard’s POPLAR project: Psychedelics Law and Regulation