I lectured on dimension theory and metric geometry at Harvard University from September 1930 until February 1931. While I was there I also tried to learn about philosophical studies parallel to those carried on in Vienna. However, while I had interesting mathematical conversations, especially with George David Birkhoff, the outstanding American mathematician, and Marston Morse, few people seemed to know much about the Vienna Circle. This changed with the arrival of Feigl, who began to propagate Viennese ideas and especially Car-nap's wherever he went.