The following statement written by Professor J. D. Goheen as a foreword to the Japanese translation of Whitehead's lectures would also be a good précis of the article. "These notes are an almost verbatim record of Whitehead's lectures in his course, Cosmologies; Ancient and Modern, on Dec. 3, 5, 8, 10, 1936. In the previous meeting of the course I had, as his assistant, given a lecture in which I asked Whitehead to make more explicit his doctrine of "vagueness". Students in the course sometimes received the impression that Whitehead disparaged clarity and advocated "vagueness" or "muddle-headedness" in philosophical thinking. Whitehead, of course, intended nothing of the kind, but he was profoundly interested in the relation of abstract tho...