Synthese (2007) 158:61–73 DOI 10.1007/s11229-006-9050-z ORIGINAL PAPER Kuhnian revolutions revisited K. Brad Wray Received: 18 December 2005 / Accepted: 8 May 2006 / Published online: 26 July 2006 © Springer Science+Business Media B.V. 2006 Abstract I re-examine Kuhn’s account of scientific revolutions. I argue that the sorts of events Kuhn regards as scientific revolutions are a diverse lot, differing in significant ways. But, I also argue that Kuhn does provide us with a principled way to distinguish revolutionary changes from non-revolutionary changes in science. Scientific revolutions are those changes in science that (1) involve taxonomic changes, (2) are precipitated by disappointment with existing practices, and (3) cannot be resolved by appealing to shared standards. I argue that an important and often over- looked dimension of the Kuhnian account of scientific change is the shift in focus from theories to research communities. Failing to make this shift in perspective might lead one to think that when individual scientists change theories a scientific revolution has occurred. But, according to Kuhn, it is research communities that undergo rev- olutionary changes, not individual scientists. I show that the change in early modern astronomy is aptly characterized as a Kuhnian revolution. Keywords Kuhn · Scientific revolution · Scientific change · Research communities · Taxonomic change 1 Introduction Kuhn’s legacy to philosophy of science is his theory of scientific change according to which the growth of scientific knowledge is punctuated by unsettling revolutionary episodes. Both historians and philosophers of science have raised concerns about the concept “scientific revolution.” Some historians suggest that “the Scientific Revolu- tion” of the early modern era was merely a rhetorical construction, and though it has figured prominently as an organizing idea in the discipline of history of science K. B. Wray (B ) Department of Philosophy, State University of New York, Oswego, 128 Piez Hall, Oswego, NY 13126, USA e-mail: kwray@oswego.edu