Professor Rudwick in his paper has given us a display of what history of science in like at its best: a mastery of the technical aspects of the subject, a sensitivity for the complexity of historical events, and all this conveyed in a language that reflects its author's appreciation of the aesthetics of style. Furthermore, I believe he has charted useful directions for conveying the richness of the materials he has dealt with. As in his past writings, his emphasis on the visual and visualization has helped us see better the topography of the social and sociological scene that he is mapping. I find the charts that he has devised insightful and very helpful; and I believe it would be very worthwhile to explore further means of representing visually the parameters that are being invoked to describe historical change. And I have not praised Professor Rudwick in order to be critical in my further remarks. What has been presented to us is an important and seminal approach to the history of science. But Professor Rudwick has attempted to do more than write elegant, very good history of science understood in the widest sense of intellectual history. He has also used his historical research into the Devonian controversy to argue a case.