Editors’ note: This essay was first published in Historical Studies in the Natural Sciences, Vol. 42, No. 5 (November 2012), 496-499. Special Issue “50 Years of The Structure of Scientific Revolutions,” edited by Michael Gordin and Erika Lorraine Milam. It is reprinted here with the permission of the author and HSNS editors.
“Structure” was a word to conjure with in 1962. Claude Lévi-Strauss’s Structural Anthropology had appeared in 1958 (translated into English in 1963); Noam Chomsky’s Syntactic Structures was first published in 1957 and had reached its fifth printing by 1965. Even if they didn’t brandish the word “structure” in their titles, a cluster of influential books in the humanities and social sciences published circa 1960 raised hopes that the complexities of, say, the plays of Racine or cultural taboos or bargaining might reveal simpler basic structures the way an X-ray revealed skeletons. The runaway success of Thomas Kuhn’s The Structure of Scientific Revolutions did its part to glamorize an already up-and-coming word. Even scholars more resistant to the lure of structuralism than linguists and anthropologists, for example historians and philosophers but also psychologists and psychoanalysts, fell under the spell of Kuhn’s structures of scientific development.
Yet probably no word strikes historians of science nowadays reading Kuhn (if they do) as more dusty and dated than the once glittering “structure.” This is not because the whole book is a fossil from a bygone era. Even if it is no longer assigned in courses across the university, much of Kuhn’s analysis still seems fresh and even avant garde: the close studies of scientific pedagogy that he flagged as crucial to understanding the cognitive and social cohesion of research communities are still a desideratum; much work in the history, philosophy, and sociology of science still focuses on the resolution of controversies as the moment when researchers’ most fundamental assumptions are laid bare; topics such as the know-how implicit in mastering scientific paradigms have been revived by the history of the body and other explorations of what is often called, not always accurately, tacit knowledge. Even though many of the polestar words that do now guide the history of science—“context,” “controversy,” “consensus”—were first made luminous in Kuhn’s Structure, “structure” itself has lost its shine.
Why? It’s not because what Kuhn meant by structure was vague or because the actual structure he proposed for narrating the history of science has been definitively falsified by subsequent research. The structure was crystalline and cyclic (but not cumulative): establishment of a paradigm, normal science pursued within that framework, growing awareness of anomalies that resist solution within the reigning paradigm, a crisis in which the coherence of both paradigm and research community frays, and the emergence and eventual triumph of a new paradigm to start the cycle anew. There was criticism aplenty of the specifics of Kuhn’s account, but by giving different answers to the questions he had posed, its effect was more to reinforce than to refute his scheme. From the outset critics worried that Kuhn’s structure might hold only for the physical sciences or that research conducted within different paradigms might not be as incommensurable as Kuhn claimed or that the crises had been melodramatized by a few well-chosen quotations. And once the word “paradigm” became the stuff of New Yorker cartoons, mandarin scholars practically broke out in hives when forced to use it. But Kuhn’s determination to wrest the definite article and majuscules away from “the Scientific Revolution” of the seventeenth century and to apply the miniscule version to many other episodes in the history of science has succeeded beyond his wildest expectations: we now nonchalantly speak of all manner of revolutions—the Darwinian, the Einsteinian, even the Genomic—even if we balk at the now vulgar “paradigm.” Kuhn’s central contention, viz. the inevitability of recurrent scientific revolutions in all fields, in the emphatic plural of his title, has become a commonplace.
So why has “structure,” the other part of the title, fared so badly, at least within the history of science? Not because Kuhn’s own version of structure has been decisively refuted, much less because an alternative pattern of historical development has replaced it. Most historians of science no longer believe that any kind of structure could possibly do justice to their subject matter. The very idea of looking for overarching regularities in the history of science seems bizarre, a kind of leftover Hegelianism, the last attempt to give Reason (now incarnate in science) a rational history—or still worse, scientism applied to science itself, more historical than Derek de Solla Price’s statistical “science of science” but just as quixotically in quest of illusory regularities. The words that have replaced “structure” among the bywords of the humanities and social sciences—terms like “culture” and “context” and “thick description”—deliberately baffle all attempts at generalizations, whether philosophical or sociological, that aspire to span places and periods. Since roughly the 1990s, the focus in these disciplines has shifted from the streamlined to the dense and detailed; the professed aim has been to “complexify” rather than simplify and to reveal variability rather than uniformity. “Focus” is used here advisedly, since the object of inquiry has contracted to ever smaller scale, both geographically and chronologically, as even a glance at the titles of articles in leading journals for the last decade or two will confirm. Even the adjectives routinely used to praise lectures index this shift in intellectual sensibility from Bauhaus (or perhaps Swedish modern) to baroque: good papers are “rich,” no longer “acute” or “incisive.”
Kuhn himself heralded this change, perhaps unintentionally and almost certainly not realizing that it would undermine a search for structures in the history of science. In a sharp and occasionally bitter 1971 article on why historians had not embraced the history of science, Kuhn placed the blame squarely on the shoulders of the historians: “The historian’s ignorance of even the main developmental stages of science has no parallel for the other disciplines on which he touches.” Yet Kuhn was unwavering in his conviction that the future of the history of science lay in history departments. This was because insofar as historians of science were at all responsible for their marginalization by historians, it was due to the “Whiggishness” inherited from the scientists’ own version of their past. Only recently, under the tutelage of Alexandre Koyré, Anneliese Maier, Frances Yates, and others, had historians of science begun to think about past science in its own terms: “For the first time, it [science] has become potentially a fully historical enterprise, like music, literature, philosophy, or law.”
That potential has been fulfilled, perhaps with a vengeance. History of science has never been more resolutely historical in its methods (archival) and modes of explanation (contextual, where the appropriate context is mostly defined by the accepted historical rubrics and specialties, e.g. “Victorian” or “postcolonial”); most of its practitioners teach in history departments, where Kuhn thought they belonged. (Whether history of science—though not the history of technology and, especially, medicine—is any better integrated into mainstream history than it was when Kuhn reproached historians for their ignorance is another question.) Yet the historicism Kuhn prophesized and welcomed has ultimately dissolved the structures he sought: an essential tension at the heart of his own still riveting vision for the history of science.
 Among the other iconic works in this vein and of this era were Roland Barthes, Sur Racine (Paris: Editions du Seuil, 1960); Mary Douglas, Purity and Danger: An Analysis of Concepts of Pollution and Taboo (New York: Praeger, 1966); and Thomas C. Schelling, The Strategy of Conflict (Cambridge, MA: Harvard University Press, 1960).
 Kuhn himself used the words “structure” and “pattern” interchangeably, as in the following description of the history of physical optics, presented as typical of all the “mature” sciences: “That pattern [of pre-Newtonian optics] is not unfamiliar in a number of creative fields today, nor is it incompatible with significant discovery and invention. It is not, however, the pattern of development that physical optics acquired after Newton and that other natural sciences make familiar today” (13).
 Kuhn himself thought this point would encounter so much resistance among readers conditioned to think of scientific development as smoothly continuous that he devoted all of chapter II to its explication.
 Derek J. de Solla Price, “The Science of Scientists,” Medical Opinion and Review I (1966): 81-97; see also Derek J. de Solla Price, Little Science, Big Science (New York: Columbia University Press, 1963). Kuhn cautiously discussed prospects for “the science of science” in Thomas S. Kuhn, “History of Science,” in International Encyclopedia of the Social Sciences, vol. 14 (New York: Macmillan, 1968), 74-83, on 82.
 Thomas S. Kuhn, “The Relations between History and the History of Science,” originally published in Daedalus 100 (1971): 271-304, and reprinted in Thomas S. Kuhn, The Essential Tension: Selected Studies in Scientific Tradition and Change (Chicago: University of Chicago Press, 1977), 127-61, on 154.
 Ibid., 150.