 In advance of applying to American universities, Feigl received letters of recommendation from Albert Einstein, Percy W. Bridgman, C. I. Lewis, and Alfred North Whitehead. Lewis wrote in his letter of April 14, 1931: “Dr. Feigl is one of the group – with Carnap, Reichenbach, and Schlick – who represents the newly formulated ‘neo-positivism,’ which represents what we in America are sure to regard as the most promising of present movements in Continental philosophy.” (Quoted in Limbeck-Lilienau 2010, p. 102) Feigl himself looking back: