A doctor and psychotherapist since 1979, Ruediger Dahlke is the author of over forty books, including Krankheit als Weg (The Healing Power of Illness), Krankheit als Sprache der Seele (Illness As a Language of the Soul), Krankheit als Symbol (Disease as a Symbol), Frauen-Heil-Kunde (The Female Healing Arts), Depression - Wege aus der Dunklen Nacht der Seele (Depression: Ways Out of the Dark Night of the Soul) and Seeleninfarkt (Breakdown of the Soul). He has established a holistic approach to psychosomatic medicine that extends into the mythical and the spiritual domains. In seminars and on tours, he leads participants into the world of spiritual imagery and motivates them to take responsibility for developing well-targeted life strategies. He is the founder of TamanGa, a healing center in Austria. In Germany, Austria, Switzerland and Italy, Dr. Dahlke regularly gives presentations on topics such as the spiritual significance of disease patterns, conscious fasting, connected breathing, meditation, and the development of spiritual awareness, as well as providing corporate training seminars. He has presented his ideas on holistic medicine and spiritual philosophy in numerous newspaper and journal articles, and in TV and radio appearances. He has also offered seminars in the United States in conjunction with The Intelligent Optimist magazine.

His goal is to support individuals along their path towards greater self-responsibility, self-determination and optimal health. His websites are www.dahlke.at and http://www.mymedworld.cc/. Thorwald Dethlefsen was a German psychologist, an esotericist, and the author of several books, who died in 2010. He practiced hypnotherapy, past-life regression and reincarnation therapy.