Yuen Ren Chao 趙元任, the historical and descriptive linguist of Chinese, wrote his doctoral dissertation on logic in Harvard’s Department of Philosophy (1918). He later recalled:
> Professor [Henry M. Sheffer] was really very meticulous; he was in > charge of my thesis on "Continuity: A Study in Methodology," concerned > with the question of the difference between a difference of degree and > difference of kind, and when it's a difference of kind, is it also a > difference of degree. > >
Quoted from an oral history interview with Rosemary Levenson, 1974. Now posted at http://content.cdlib.org/view?docId=hb8779p27v&chunk.id=div00023&brand=calisphere&doc.view=entire_text . Accessed 20111129.
I remember at the defense of the thesis, at which Professor William Ernest Hocking was chairman, after they announced that I had passed the examination, Professor Hocking asked me, "Do you feel that writing on such a subject has had any effect on your life?" I said, "Certainly it didn't help me in my habits of indecision."
[from First "Green Letter", Peking, 1921:] [My dissertation] prov[ed] that it was impossible to prove anything and conclud[ed] that no universal proposition was true.