The Zollikon Seminars were a series of philosophical seminars delivered between 1959 and 1969 by the German philosopher Martin Heidegger (1889–1976) at the home of Swiss psychiatrist Medard Boss (1903–1990). The topic of the seminars was Heidegger's ontology and phenomenology as it pertained to the theory and praxis of medicine, psychology, psychiatry and psychotherapy. The protocols of the seminars, along with correspondences between Heidegger and Boss, were published in German in 1987 under the title Zollikoner Seminare, Protokolle- Gersprache- Briefe Herausgegeben von Medard Boss (note 382 pages). The English version of the text was published in 2001 (360 pages). Note the later German publication of the HGA 89. Zollikoner Seminare, (2017) is 880 pages and more complete. The complete HGA 89 Table of Content is here. Background Boss was a psychoanalytic psychiatrist trained within the framework of natural scientific medicine. During active military duty as a field doctor during World War II (which "all Swiss men who were not psychologically impaired were required to do"), Boss read Heidegger's dense and often complicated text, Being and Time. He initially remarked that he "understood almost none of its content". Yet, as a psychiatrist, Boss was captivated by the ideas, which he evaluated as "fundamentally new, unheard of insights into the human being's way of existing in the world", and was intrigued by the author. Following World War II, Boss inquired about Heidegger, at which he was informed about Heidegger's participation in the Nazi Party and was discouraged from entertaining Heidegger's philosophy. However, Boss attempted to distinguish between Heidegger's philosophy and Heidegger's character, and, after evaluating the former, decided to write Heidegger a letter. In 1947, Boss wrote Heidegger, asking him to clarify some of his philosophical ideas. To Boss's surprise, Heidegger replied. For the next twelve years, Boss and Heidegger corresponded about by mail and personal visits. Boss, though, "did not feel it proper to be the only one benefitting from frequent meetings with a great thinker." With Heidegger's permission, Boss opened up their discussions with colleagues and students, beginning the Zollikon Seminars. The Seminars The Zollikon Seminars were conducted intermittently, "two to three times per semester", between 1959 and 1969. Boss noted that Heidegger dedicated three hours a night, two nights a week to the task, and typically spent the day before preparing the lectures. Typically, fifty to seventy of Boss's psychiatric colleagues and students were invited to the lectures. The