Terence Kemp McKenna (November 16, 1946 – April 3, 2000) was an American philosopher,
psychonaut, researcher, teacher, lecturer and writer on many subjects, such as human
consciousness, language, psychedelic drugs, the evolution of civilizations, the origin and end of the universe,
alchemy, and
extraterrestrial beings.
Terence McKenna was an Ethnobotanist. He loved plants and was fascinated with the relationship between humans and plants. He conducted fastidious research on the similar molecular structures of the active ingredients in certain plant hallucinogens and neurotransmitters in the human brain. For his research into Time and the I Ching, he worked with his brother Dennis, also an ethnobotanist and ethnopharmacologist. Because Terence openly admitted to acquiring many of his insights while under the influence of hallucinogens, much of his work is often trivialized or minimized. This is due to personal opinions around drug use. It is unfortunate since Terence was a genius doing serious work, his most original being his work with Time and the I Ching.
For Terence the psychedelic journey was a shamanic tradition. He believed if a person journeys into the otherworld made evident by the hallucinogenic experience, they go as a representative of our species. They are not going for their own pleasure, but for the benefit of their culture and community. They are shamans retrieving information, interpreting it and bringing it back to the community as something useful.
In 1971 Terence and Dennis Mckenna took a trip to Colombia to try to explore the landscape made evident by the psychedelic experience more fully and came back with information about Time and the I Ching. This journey is explored in the book, True Hallucinations.
Though often thought of as a simple divination tool, Mckenna called the I Ching one of the “oldest structured abstractions known.” I Ching symbols have been found scratched on the 6,000 year old shoulder
More:
http://www.ritualgoddess.com/the2012vortex/?p=2187