Early life and education in Germany; student years in U.S. and A.B., Midland College, 1924; M.Sc., University of Nebraska, 1927; Ph.D., Yale University, 1929. Discussion of change in interest from liberal arts to physics. Sterling Research Fellow in Germany working with Arnold Sommerfeld, Hans Bethe, Erwin Schrd̲inger, Max Born and Fritz London on electron theory of metals and Van der Waal's forces. Instructor, 1929-1930; Professor, Yale University beginning 1931; changes in physics curriculum and resistance to it by Leigh Page. Physics textbooks written by Margenau. Work at Yale during World War II, present work being done such as plasma physics, line broadening, philosophy of physics. Reminiscences of associates including Eugene Wigner, John Wheeler, Percy W. Bridgman. Extensive discussion of philosophical views, notably philosophy of science and historical methodolgy, and influences on these views.