Aleister Crowley (1875-1947), also known as "The Great Beast" and the "Wickedest Man in the World" was one of the most profound students of Magick, Qabalah and Yoga. His vast influence reaches through all modern occultism. He is widely recognised as the first Western investigator to give initiation a truly scientific method. In reconciling occultism to physical science, mathematics and philosophy, Crowley achieved a lasting synthesis that remains unsurpassed for depth of insight and comprehensiveness. Christopher S Hyatt, Ph.D. was trained in both psycho-physiology and clinical psychology and practised as a psychotherapist for many years. He has published many articles in peer-reviewed, professional journals. Today he is known as the world-famous author of a wide variety of books on psychology, sex, tantra, tarot, self-transformation and Western magic. Lon Milo DuQuette lives in Costa Mesa, California. James Wasserman specialises in esoteric literature and currently works in book production and graphic design. He lives in New York City. Mark Stavish is the Director of Studies for the Institute for Hermetic Studies.