Christian R�tsch, Ph.D., is a world-renowned anthropologist and ethnopharmacologist who specializes in the shamanic uses of plants. He is the author of Marijuana Medicine and coauthor of Plants of the Gods, Shamanism and Tantra in the Himalayas, Witchcraft Medicine, and The Encyclopedia of Psychoactive Plants. He lives in Hamburg, Germany, and lectures around the world.
Alex Grey is a renowned American artist specializing in spiritual and psychedelic (visionary) art. His work spans a variety of forms including performance art, sculpture and painting. He is a member of the Integral Institute, on the board of advisors for the Center of Cognitive Liberty and Ethics and is Chair of Wisdom University's Sacred Art Department. He and his wife Allyson Grey are co-founders of the Chapel of Sacred Mirrors, CoSM, a non-profit church supporting Visionary Culture in Wappinger, New York.