Abstract
Thomas Kuhn
Chicago: University of Chicago Press, 1962
An obstruction to wisdom and a recipe for science
The structure of scientific revolutions by Thomas Kuhn was the most influential book on the nature of science in the second half of the 20th century. It has sold a million copies in 20 languages since it first appeared as the final instalment of the logical positivists’ International Encyclopedia of Unified Science (IEUS) in 1962. A peculiar feature of the book's reception is that it has been most popular with humanists and social scientists, even though Kuhn thought he had nothing of interest to say to them – except that their knowledge pursuits failed to fit his cyclical model of normal and revolutionary science. In striking contrast, Kuhn singularly failed to persuade the physicists in whose subject he was professionally trained and whose history provides the primary data for his model. Indeed, I believe that future historians will treat the massively unintended significance of Structure as symptomatic of the West's neurotic relationship to science in the 20th century. Nevertheless, it must be admitted that Structure is a remarkably self-exemplifying text, since Kuhn correctly – if again unwittingly – identified the key psychosocial mechanism responsible for his own book's success.
If, as Socrates believed, the recognition of one's own ignorance is the first step on the road to wisdom, then Structure has proven to be an obstruction. The book did much to establish the relevance of the history of science to an understanding of contemporary science, but without encouraging its readers to check the accuracy or applicability of Kuhn's particular version. As someone who has recently published a comprehensive critique of Structure[1], I am frequently faced with readers who claim to have found in Kuhn's account of paradigm formation a compelling model for their own disciplines. Typically, these readers come to Structure with a rather patchy and personalized understanding of the histories of their own disciplines. More importantly, they have no other general account of the history of science with which to compare Kuhn's account or, when they do, the alternative account is a highly simplified and judgemental version of positivism that casts their own disciplines in a harshly negative light. Not surprisingly, they quickly embrace Kuhn and never look back. In this respect, it actually helps that Kuhn's model is anchored in physics, since the same applies to the positivist model, and so it becomes easy to conclude that Kuhn marks a significant improvement.
Kuhn appeared to provide a salutary recipe for turning one's activities into a science. One only had to obtain agreement on a common theoretical and methodological framework within which permissible problems and their solutions are clearly defined. In a word: a paradigm. In contrast, positivism in its vulgarized form seemed to demand that a science also exercise instrumental control over some part of the natural world. This additional requirement proved to be a step too far for most humanists and social scientists. Not only did they lack the conceptual and material resources to render their inquiries ‘instrumental’ in the relevant sense, but many also objected to the moral implications of such a world-view when applied to human beings. As it happens, the latter turns out to be not so far from Kuhn's own interest in defining progress in science by referring only to criteria that the scientists themselves have designed. To many of Kuhn's philosophical opponents, this move smacked of ‘relativism’. However, it was made in the same spirit that had motivated the logical positivists to lay down principles of verification, falsification, and operationalization. Despite their technical differences, these criteria and principles all presuppose that scientists define the rules of their own game, one that is insulated from the causes and effects of the larger reality in which they are embedded.
Kuhn and the positivists: alternative reaction formations
In canonical presentations of the history of modern philosophy of science, Kuhn and the logical positivists are portrayed as holding diametrically opposed views. Basically, Kuhn defined science historically and sociologically, whereas the positivists defined it logically and empirically. However, this difference is relatively superficial vis-à-vis their commonalities. Indeed, the doyen of logical positivism, Rudolf Carnap, regarded the project of Structure as complementing his own. He had no problem including the book as part of the IEUS, which became positivism's collective legacy [2]. Moreover, Kuhn returned the compliment by increasingly orienting his research toward technical problems in analytic philosophy of mind and language, which was how the positivist project flourished in the American academy. By the time Kuhn retired as the Rockefeller Professor of Philosophy and Linguistics at MIT in 1992, his much vaunted ‘historicism’ had been reduced to the sprinkling of stylised, self-serving historical examples commonly found in mainstream philosophy of science [e.g. 3].
Neither Kuhn nor the positivists ever fully acknowledged the technological dimension of modern science, where science most naturally interfaces with our prescientific understanding of reality. Even when Kuhn and the positivists wrote about scientific experiments, their focus remained fixed on the role of experiments in generating data or testing theories, not on their material character as, say, an economist concerned with ‘externalities’ would treat experiments. In particular, Kuhn and the positivists made a point of not asking whether the instruments used in experiments were inspired and/ or applied in a military-industrial setting outside the experimental context.
From a psychiatric standpoint, the accounts of science put forward by Kuhn and the logical positivists were reaction formations in response to traumas that had dealt severe blows to their normative ideals of science. The traumas were the 20th century's two world wars. In their early 20s, Carnap had served in World War I and Kuhn in World War II. Both began life as aspiring physicists, but physics failed them in wartime. The discipline that they understood to be natural philosophy by more exact means turned out to be a compliant accessory to mass destruction. In response, both promoted excessively idealized visions of science that were the opposite of the tendencies they rejected in the science of their day.
Carnap had been inspired by the Einsteinian revolution, in which science broke genuinely new philosophical ground by reconceptualizing the nature of space and time. However, he was disappointed by the ease with which, less than a decade later, the German physics community fell into line with the patriotic sentiments of practitioners of the inferior science of chemistry to enlist in the Kaiser's cause. In response, Carnap attempted to justify physical knowledge without making any reference to its applications. His model was the successful attempt by mathematicians to declare disciplinary independence from physics and engineering in the 19th century by rediscovering their Euclidean roots in deductive proof theory. Here Carnap had been influenced by his old teacher Gottlob Frege and especially his fellow war veteran, Ludwig Wittgenstein, a self-loathing engineer who was heir to Austria's leading steel-making family. In the interwar years, Wittgenstein intermittently attended the meetings of the Vienna Circle in which logical positivism's tenets were crystallized [4].
Kuhn's original inspiration, interests, and ultimate disillusionment were similar to Carnap's. Kuhn spent World War II jamming German radar signals in East Anglia and thereafter resolved not to pursue a career in physics once he completed his Ph.D. Physics in its nascent ‘Big Science’ mode no longer held its original attraction, and so he moved to the history and philosophy of science. Not surprisingly, Kuhn eventually admitted that he was interested in the history of science solely as a sustained instance of pure inquiry (not, say, as an engine of wealth production or a bulwark of national defence). This was in response to a question about whether he ever felt compelled to change his model in light of the changes in the scale and scope of the physical sciences in the second half of the 20th century [5]. After all, virtually all of Kuhn's historical examples had been taken from the period 1620–1920, though Kuhn himself was professionally trained in more recent developments. Interestingly, Kuhn not only felt no need to revise his perspective but he equally felt no need to criticize contemporary science for failing to adhere to his account. It fell to others to follow those leads, typically without Kuhn's support and sometimes with his active opposition [e.g. 6].
Kuhn's successful disengagement from criticism of science, based on his work and even the criticism that others made of his work, was indicative of his privileged academic position. This privilege was, in turn, rooted in his long-term mentorship under Harvard President James Bryant Conant, a major architect of US Cold War science policy and the person to whom Structure is dedicated. Conant enabled the disenchanted Kuhn to make the transition from physics to the humanities by finding him a job in the newly created ‘General Education in Science’ programme, where Structure's theses were honed. For Conant, the scientific idealism of Kuhn and other disenchanted young physicists (e.g. Gerald Holton) was a key ideological component to the appeasement of nonscientists in an age when science was to play an increasingly formidable role in public affairs. Kuhn's refusal to back self-declared ‘Kuhnians’ who denounced science's complicity in the military-industrial complex may be plausibly read as tacit endorsement of Conant's ‘dirty hands’ image of a politically compromised science as a stabilizing force in a world on the brink of nuclear war [1], pp. [150–226].
The differences between Kuhn and his positivist forebears lie in their specific reaction formations. Carnap and his fellow logical positivists retreated to mathematical formalism, while Kuhn and most of the current generation of science studies practitioners have had recourse to historiographical purism. The clearest symptom of this purism is a studied refusal to involve present-day judgements in accounts of past science. Before Kuhn, it had been common to narrate the history of science in terms of a mix of obstacles and breakthroughs that eventuate in today's knowledge, which, albeit imperfect, is presumed to be the best yet. After Kuhn, however, one tells the history entirely from the standpoint of the original agents, without passing judgement on the long-term significance of their actions. Indeed, for Kuhn, a proper understanding of a science's significance is possible only once its major disputes have been resolved, and the historian arrives on the scene as a spectator, not a participant. In the annals of Kuhn criticism, this reaction formation has been philosophised as ‘the incommensurability thesis’. While this thesis has helped to undermine the sorts of triumphalist histories that scientists have told to raise funds and exert influence, it has carried an important cost: historical understanding would seem to require the abandonment of one's own world-view. Kuhn himself compared the switching back and forth between the past and the present to bilingualism [7], pp.[231–278].
Kuhn unfortunately vindicated by his own theory
The incommensurability thesis operates also at a deeper level that helps to explain Structure's success. For Kuhn, the ability to understand the world through two radically different paradigms is not only a skill imparted to fledgling historians of science, but also a mental capacity that was originally present in such scientific revolutionaries as Galileo and Einstein. Kuhn's interesting and controversial point here is that very few scientists actually have this capacity because it is not part of their normal training. Consequently, the main cause of revolutionary change in science is that subsequent generations are taught only the new and not the old paradigm. Of course, this process does not happen overnight, but its implications are clear. Argumentation in science does more to sway uncommitted spectators, especially if they are young or newcomers to the field, than to change the minds of the scientific principals themselves. The sheer fact that newcomers have not yet personally invested in the old paradigm is typically sufficient to make them open to a radical change in direction. From that perspective, matters of ‘tradition’, ‘track record’, ‘accumulated wisdom’, and ‘presumption’ are myths perpetuated in scientific textbooks to indoctrinate the young in the dominant paradigm. However, as Kuhn points out, these myths need to be reinvented after each scientific revolution in a manner akin to the periodic rewriting of history recounted in Orwell's 1984[8], p.167].
When considering the version of their collective history that scientists promote among themselves and in the larger public – a version that the logical positivists largely rationalized – Kuhn adopted an attitude similar to Freud's. Kuhn did not denounce scientists for their self-serving historiography but rather tried to understand its function as a coping mechanism for a practice whose maintenance requires the violation of its avowed principles. After all, science advertises itself as the epitome of rationality, which at the very least implies that people will change their minds in the face of logic and evidence. However, if scientists literally acted on such scruples, then the research frontier would change too often for any clear sense of progress to be registered. New ideas in their initial formulation can rarely survive critical scrutiny, so it becomes important that people sympathetic to those ideas are given an opportunity to develop them. Scientific revolutions ultimately occur because the minds of different people start to matter. Although Kuhn confined his own development of this insight to the cognitive processes by which new recruits acquire a paradigm, the idea that new lines of inquiry require new personnel pointed toward a more biologically inspired, even Darwinian-selectionist, model of scientific change. In effect, Kuhn has helped to erase a traditional mark of the human in the animal kingdom, namely, that our ideas can live and die in our stead.
Kuhn's great nemesis, Karl Popper, strenuously objected to the profoundly pessimistic vision of human rationality depicted in Structure[7], pp.[51–58]. While Popper granted that revolutionaries like Galileo and Einstein BOOKS RECONSIDERED 827 were more the exception than the rule in the history of science, he interpreted what Kuhn benignly called ‘normal science’ as a moral failure, not a successful adaptation strategy. Unfortunately, 40 years later, Kuhn seems to have had the last laugh. The story of Structure's reception in the philosophical community is a tale of two halves, which together provide a striking confirmation of his own generation-based account of intellectual change. The first 20 years consisted of an array of negative responses, ranging from Popperian high dudgeon to more pedantic charges of ambiguity and inconsistency. In the last 20 years, however, a new generation has come to dominate the science studies disciplines. They take Structure as the unproblematic foundation for its inquiries – as if the original criticisms had never been made. In any case, Kuhn certainly never answered the criticisms, and the current generation is sufficiently beholden to Structure not to want to revive them.
In their ‘Kuhnified’ state, philosophers of science are prone to see themselves as ‘underlabourers’ who clarify, defend, but never question the dominant paradigms, unless the scientists themselves have done so first [1], pp.[260–317]. The general philosophy of science pursued by Popper, the positivists, and even Kuhn himself has given way to multiple philosophies of the special sciences. Overriding concerns about rationality and progress have been replaced by more technical analyses of the relationship between evidence and inference in particular fields. Even today's overheated turf battles between philosophers and sociologists of science turn on little more than who is more properly immersed in the scientific practices under investigation: Does taking a few science courses measure up to spending a few months observing a laboratory? The old idea that an outsider might criticize science for failing its own publicly avowed standards is virtually unthinkable today. For those who have inherited Kuhn's Cold War belief that normal science is a bulwark in a volatile world, then it is only to be expected that philosophers today will be quicker to criticize Creationists for violating evolutionary strictures than evolutionists for violating more general scientific criteria of proof and explanation (an activity for which Popper and the positivists became notorious).
An overall assessment of Structure's impact would have to conclude that the book has enabled disciplines on the institutional defensive to legitimize themselves as ‘sciences’, at the cost of deflecting discussion from the larger normative questions surrounding science's place in contemporary society. In this sense, Kuhn may be said to have had a ‘repressive’ effect. But it is an effect that can be detected only if we retain the pre-Kuhnian idea that intellectual life harbours a collective memory that is sustained across generations, often in spite of what most individuals find convenient to believe. After all, the social psychology that underwrites a Kuhnian paradigm is none other than the experimental demonstrations of group conformity that were in vogue during the Cold War [9], pp.[171–174, 262–285].