From the mythical beverages described in the founding texts of Eastern religions, to the altered states of consciousness of the greatest prophets, to the original nature of the Christian eucharist, Stephan Schillinger explores what Huston Smith, the most influential religious historian in 20th century, called ´the best kept secret in history´. He will shares his reflection on the origin of spirituality and the major religious traditions that followed. His demonstration explores groundbreaking questions and assumptions about the nature of reality and psychedelic experiences leading to the expanded states of consciousness he proposes as the very origin of spiritual feeling. He reveals the burnt bridges between two shores. One abandoned, that of the sacred, psychedelic and entheogenic plants that we rediscover here, under the light of science. And the other, place of most spiritual traditions and religions, objects of many misinterpretations.