Like Descartes and Pascal, Hans Hahn (1879–1934) was both an eminent mathematician and a highly influential philosopher. He founded the Vienna Circle and was the teacher of both Kurt Gödel and Karl Popper. His seminal contributions to functional analysis and general topology had a huge impact on the development of modern analysis. Hahn’s passionate interest in the foundations of mathematics, vividly described in Sir Karl Popper’s foreword (which became his last essay), had a decisive influence upon Gödel. Like Freud, Musil and Schönberg, Hahn became a pivotal figure in the feverish intellectual climate of Vienna between the two wars. Volume 1: The first volume of Hahn’s Collected Works contains his path-breaking contributions to functional analysis, the theory of curves, and ordered groups. These papers are commented on by Harro Heuser, Hans Sagan, and Laszlo Fuchs. Volume 2: The second volume deals with functional analysis, real analysis and hydrodynamics. The commentaries are written by Wilhelm Frank, Davis Preiss, and Alfred Kluwick. Volume 3: In the third volume, Hahn’s writings on harmonic analysis, measure and integration, complex analysis and philosophy are collected and commented on by Jean-Pierre Kahane, Heinz Bauer, Ludger Kaup, and Christian Thiel. This volume also contains excerpts of Hahn’s letters and accounts by his students and colleagues.

Like Descartes and Pascal, Hans Hahn (1879–1934) was both an eminent mathematician and a highly influential philosopher. He founded the Vienna Circle and was the teacher of both Kurt Gödel and Karl Popper. His seminal contributions to functional analysis and general topology had a huge impact on the development of modern analysis. Hahn’s passionate interest in the foundations of mathematics, vividly described in Sir Karl Popper’s foreword (which became his last essay), had a decisive influence upon Gödel. Like Freud, Musil and Schönberg, Hahn became a pivotal figure in the feverish intellectual climate of Vienna between the two wars. Volume 1: The first volume of Hahn’s Collected Works contains his path-breaking contributions to functional analysis, the theory of curves, and ordered groups. These papers are commented on by Harro Heuser, Hans Sagan, and Laszlo Fuchs. Volume 2: The second volume deals with functional analysis, real analysis and hydrodynamics. The commentaries are written by Wilhelm Frank, Davis Preiss, and Alfred Kluwick. Volume 3: In the third volume, Hahn’s writings on harmonic analysis, measure and integration, complex analysis and philosophy are collected and commented on by Jean-Pierre Kahane, Heinz Bauer, Ludger Kaup, and Christian Thiel. This volume also contains excerpts of Hahn’s letters and accounts by his students and colleagues.