Hans Hahn and the Foundational Debate

摘要: “I am not much given to emotions”, wrote the 30-years old mathematician Hans Hahn in 1909 physicist Paul Ehrenfest, who lived St. Petersburg, “but a friend is as far away you are, I confess it: sometimes, when have attempted dip into metaphysics of Aristotle, felt awe-struck, and regret lack opportunities ponder these things depth, pondered calculus variations.”1 In due course, however, managed create those for philosophical studies which he longed so much; died some twenty-five years later, Philipp Frank could describe him true founder Vienna Circlet.2