Reviewed by: Nicolai Hartmanns Dialoge 1920–1950. Die “Cirkelprotokolle.” ed. by Joachim Fischer and Gerald Hartung Keith R. Peterson Joachim Fischer and Gerald Hartung, editors. Nicolai Hartmanns Dialoge 1920–1950. Die “Cirkelprotokolle.”Berlin: Walter de Gruyter, 2020. Pp. v + 487. Hardback, $126.99. Originally a student of Marburg Neo-Kantianism, Nicolai Hartmann (1882–1950) departed from this tradition to become one of the leading German philosophers of the first half of the twentieth century. He wrote on all the major fields of philosophy, including the philosophy of history, epistemology, ethics, and aesthetics, although his central interest was ontology. He held teaching posts in Marburg, Cologne, Berlin, and Göttingen, and was president of the German Philosophical Association after the Second World War. Perhaps unique among his peers, he spearheaded the resurgence of ontology by developing a pluralistic, humanistic realism that attempted to do justice to both the sciences and the humanities. Over the last twenty years, after a long period of neglect, his work has been attracting more attention from an international group of scholars. Until now these scholars have relied on Hartmann’s many published works. However, after his literary estate was delivered to the Archive of German Literature in Marbach, Germany, in 2012, scholars discovered files full of dozens of transcripts of conversations held during evening meetings of graduate students and colleagues that Hartmann held at his own home throughout his career. This book contains six of the roughly fifty collections of “protocols” (discussion minutes), and is a product of a four-year Deutsche Forschungsgemeinschaft grant (2016–20). The transcribed remainder will be made available through De Gruyter’s website at some point in the future. This nearly five-hundred-page volume includes, in addition to the text of the dialogues, informative editorial introductions and an appendix that all together constitute roughly 165 pages. These are made up of several useful elements: introductory “abstracts” for each dialogue; an editors’ report on the mechanics of the edition, its goals, and the scope of the discovery (about 2,800 pages of hand- or typewritten text); a discussion of the protocol as a genre; biographical entries on the participants in the dialogues included in this volume (here 41 of 115 participants over the years); a bibliography of Hartmann’s works; and a valuable list of all of the lecture courses Hartmann delivered at his university posts from 1919 to 1950 in Marburg, Cologne, Berlin, and Göttingen. The topics of the dialogues included in this volume are (1) “The Essence of Ideal Being” (1923–24); (2) “On the Nature of Essence” (1925–26); (3) “Intuition and Concept” (1931); (4) “What Are Aesthetic Values?” (1939–40); (5) “On Spiritual and Mental Being” (1942); and (6) “On Thinking” (1948). Some of the editors’ criteria for including a dialogue in the volume were the relevance of its content generally and for understanding Hartmann’s work, whether it included a diversity of themes covering various fields, the richness of controversies in it, or the appearance of significant participants. Regarding the last point, the editors consider the dialogues a valuable resource for writing a history of early twentieth-century German philosophy, since figures like Hans-Georg Gadamer (who participated in no less than five separate discussion groups spanning four years during his time in Marburg), Helmuth Plessner (who was an enthusiastic participant in the circle during Hartmann’s time in Cologne), and Günter Patzig (respected Aristotle scholar and Frege advocate in Göttingen), among others, participated in these meetings. The introduction outlines five main reasons why these protocols constitute an important discovery for both Hartmann scholars and historians of early twentieth-century philosophy. [End Page 519] First, they display the vast range of philosophical problems and fields with which Hartmann was familiar and actively attempting to deal, from epistemology and philosophy of science to ethics, aesthetics, philosophical anthropology, and ontology. Second, they show him engaging in extended dialogue with others over these topics, where ideas are tested and thoroughly submitted to criticism. While it appears from his lengthy tomes that Hartmann was a monological thinker, his persistent cultivation of these groups throughout his entire career and testimony from others show that he had a real...