Abstract Victorio Hosle called Hans Jonas “the last German philosopher.” Jonas’ Memoirs connect changing philosophical priorities with devastating life events. The shock of learning of his former mentor, Heidegger’s, affiliation to National Socialism, his exile from Germany and his mother’s death in Auschwitz, made the conceptual universe of German Idealism, Husserl and Heidegger, seem nihilistic and akin to a Gnostic denigration of worldliness. The brutal wartime realities exposed a callous removal from nature and any meaningful humanism. After soldiering in the war with “Maccabean rage,” he subsequently created his philosophical biology of organism, one which respected the corporeal, metabolic basis of life. His consequent innovations in Environmental and Medical Ethics had an enormous impact on the German scholarly world. Jonas retained a lifelong attachment to German culture and “saved” German philosophy by making critical amendments. Later in life he wrote in German, spent a sabbatical year in Germany, received the medal of honor from the Federal Republic of Germany and honorary doctorates from several German universities. The “German” Jonas brought a respect for ontology and nature to a philosophy that was prone to sterile abstractions. The life-affirming “Jewish” Jonas restored an ethical mandate for responsibility for the future of the planet and humankind to a bereft ethics.