Thomas Kuhn and Science Education
Michael R. Matthews
Beginning 60 years ago, Thomas Kuhn has had a significant impact across the academy and on culture more widely. And he had a great impact on science education research, theorising, and pedagogy. For the majority of educators, the second edition ...
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PubMed Central (PMC)
Sci Educ (Dordr). 2022 Dec 13 : 1–70.

doi: 10.1007/s11191-022-00408-1 [Epub ahead of print]

PMCID: PMC9745714

PMID: 36531747

Thomas Kuhn and Science Education

Learning from the Past and the Importance of History and Philosophy of Science

Michael R. Matthews

School of Education, University of New South Wales, Sydney, NSW 2052 Australia

Find articles by Michael R. Matthews

School of Education, University of New South Wales, Sydney, NSW 2052 Australia

Michael R. Matthews, Email: ua.ude.wsnu@swehttam.m.

Corresponding author.

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Abstract

Beginning 60 years ago, Thomas Kuhn has had a significant impact across the academy and on culture more widely. And he had a great impact on science education research, theorising, and pedagogy. For the majority of educators, the second edition (1970) of his Structure of Scientific Revolutions (Kuhn, 1970a) articulated the very nature of the science, the discipline they were teaching. More particularly, Kuhn’s book directly influenced four burgeoning research fields in science education: Children’s Conceptual Change, Constructivism, Science-Technology-Society studies, and Cultural Studies of Science Education. This paper looks back to the Kuhnian years in science education and to the long shadow they cast. The discipline of science education needs to learn from its past so that comparable mistakes might be averted in the future. Kuhn’s influence was good and bad. Good, that he brought HPS to so many; bad, that, on key points, his account of science was flawed. This paper will document the book’s two fundamental errors: namely, its Kantian-influenced ontological idealism and its claims of incommensurability between competing paradigms. Both had significant flow-on effects. Although the book had many positive features, this paper will document how most of these ideas and insights were well established in HPS literature at the time of its 1962 publication. Kuhn was not trained in philosophy, he was not part of the HPS tradition, and to the detriment of all, he did not engage with it. This matters, because before publication he could have abandoned, modified, or refined much of his ‘revolutionary’ text. Something that he subsequently did, but this amounted to closing the gate after the horse had bolted. In particular, the education horse had well and truly bolted. While educators were rushing to adopt Kuhn, many philosophers, historians, and sociologists were rejecting him. Kuhn did modify and ‘walk back’ many of the head-turning, but erroneous, claims of Structure. But his retreat went largely unnoticed in education, and so the original, deeply flawed Structure affected the four above-mentioned central research fields. The most important lesson to be learnt from science education’s uncritical embrace of Kuhn and Kuhnianism is that the problems arose not from personal inadequacies; individuals are not to blame. There was a systematic, disciplinary deficiency. This needs to be addressed by raising the level of philosophical competence in the discipline, beginning with the inclusion of HPS in teacher education and graduate programmes.

Keywords: Thomas Kuhn, Relativism, Idealism, Constructivism, Philosophy

Introduction

Thomas Kuhn’s impact on science education has been immense. This is reflected in the opening sentence of a 2022 article by David Treagust, one of Australia’s foremost science educators:1

Perhaps one of the major influences on our understanding of how scientific research and scientific knowledge evolves and develops was the publication of Thomas Kuhn’s (1962) The Structure of Scientific Revolutions. This small book really changed the way we look at the enterprise that is science. (Treagust, 2022, p.16)

Treagust spoke for the science education research community. In Peter Fensham’s landmark study of the discipline of science education, leading science educators repeatedly identify Kuhn’s Structure as the main influence on their understanding of science (Fensham, 2004). Richard Duschl, in 1990, described Structure as ‘the most acclaimed book in history of science’ (Duschl, 1990, p.36).2

The immediate educational impact of Structure was on educators’ understanding of the nature of science (NOS) which is, increasingly, a stand-alone inclusion in worldwide national and provincial science curricula.3 An explicit or implicit view of NOS informs curricular decisions, pedagogical practices, and wider national policies about the extent, duration, and funding of science in schools and beyond. It is widely agreed that students learning science should learn what science is, how it works, and what it accomplished. In brief, they should learn the nature of science. This is a truism, but its implication, namely, that science students and teachers need to learn the history and philosophy of science (HPS), has been less recognised and followed through. The seldom faced question is: How is it possible to learn about NOS without knowledge of HPS?

Many educators who, after the publication of the second edition of Structure in 1970, did look for history and philosophy of science, saw just Kuhnianism, more particularly Kuhn-inspired constructivism. It is important to distinguish Kuhn’s understanding of NOS from the many versions of Kuhn-inspired NOS. At many points, Kuhn was at pains to separate his views from those being advanced in his name. ‘Kuhnianism’ is an appropriate inclusive label for the latter. It includes Kuhn’s genuine views but also those mistakenly advanced in his name. In education, Kuhnian NOS not only informed, but it also underpinned Science-Technology-Society (STS) curricula and Cultural Studies in Science Education research and framed the narrative about inclusion of indigenous science within school science programmes.

Kuhn’s Structure not only dealt with revolutions in the history of science but also painted a revolutionary account of the nature and practice of science. But did Kuhn give a correct account? Many in HPS thought he did not. For the million-plus who bought the book,4 reading Structure was a Rorschach test. Kuhn recognised this. In 1969, at a large Frederick Suppe-organised symposium on ‘The Structure of Scientific Theories’ Kuhn, reflecting on the reception of the first edition, wrote:

I have sometimes found it hard to believe that all parties to the discussion had been engaged with the same volume. Part of the reason for its success is, I regretfully conclude, that it can be too nearly all things to all people. (Kuhn, 1977c, p.459)

He regretted the book’s ‘excessive plasticity’, particularly blaming his casual introduction of the term ‘paradigm’ (ibid). He should, more to the point, have regretted writing unclear and sloppy sentences about vital subjects. Philosophers, above all, need be cognisant of the importance of clarity in writing.

The argument of this paper is that the most important lesson to be learnt from the problems of science education’s wholesale embrace of Kuhnianism is the pressing need to raise the level of philosophical competence in the discipline, beginning with the inclusion of both history and philosophy of science, and philosophy of education, in science-teacher education programmes, and in education doctoral programmes.

Kuhn’s Status

It is oft claimed that Thomas Kuhn was the twentieth century’s most influential historian of science. This can hardly be disputed. He was a Harvard-trained physicist5 who published a great deal over a 55-year span.6 However, his global reputation was based upon one book—The Structure of Scientific Revolutions—which was first published in 1962 as a monograph in a little-read Vienna Circle-inspired International Encyclopedia of Unified Science,7 and then, eight years later, republished as a stand-alone second edition by University of Chicago Press (Kuhn, 1970a). The second edition precipitated the Kuhnian tsunami. Structure was quickly translated into two-dozen languages and sold over a million copies. In Australia’s Arts and Humanities Citation Index, it was the most cited book on any subject through the 1970s and 1980s. In the USA, the Social Science Citation Index listed 4970 Kuhn citations in just the decade 1971–1981 (Brush, 2000, p.54). Doubtless, it held much the same position in comparable indexes in other countries, both English-speaking and otherwise. Google Scholar, in October 2022, listed 71 versions of the book, having 143,303 citations.

For a combination of philosophical, sociological, and cultural reasons, the book had stratospheric sales and influence; sales way beyond that of almost any other HPS book published in the twentieth century; and probably beyond all HPS books. David Hull observed: ‘All the wrong people seemed attracted to his book for all the wrong reasons’ (Hull, 1988, p.112). There have been efforts to give a sociological or naturalist account of the explosion of Kuhnianism: Why was the book such a huge publishing success, and why did the constellation of ideas it contained spread so widely and quickly while its components had sat in isolation for decades?8

Some regard Kuhn as ‘the most influential philosopher writing in English since 1950, even the most influential academic’ (Sharrock & Read, 2002).9 For others, he is ‘one of the historically most significant philosophers of the twentieth century’ (Bird, 2000, p.vii). Kuhn’s vocabulary (‘paradigm’, ‘paradigm shift’, incommensurability’, ‘gestalt’) and thought-to-be Kuhnian ideas (scepticism, relativism, subjectivism, science as power play) have become a part of everyday culture. As recently as 8 October 2022, a correspondent writing on a local political issue, in The Age, a major Australian newspaper, confidently related that:

Thomas Kuhn’s The Structure of Scientific Revolutions … exposed the influence of inertia, interests and the irrational on scientific explanation and understanding. (p.34)

And this is 60 years after the book’s publication. Countless readers of the newspaper would be nodding their heads. Most of them not asking: What is the extent and degree of such influences? Were the influences determinate, or otherwise, of scientific explanations and understandings? Were they were brought to light and corrected? Science educators also nodded their heads, and very few followed through with the obvious questions. Gerald Doppelt gave an accurate, and neutral, account of Kuhn’s impact:

Putting the merits of Kuhn’s philosophical claims to one side, it is still undeniable that his work has reshaped the terms of debate, and much research, in philosophy. In short, his work had given a new centrality and relevance to the history of science, and the examination of specific scientific practices, for philosophers. (Doppelt, 2001, p.160)

This paper does not put Kuhn’s philosophical merits to one side: It appraises them, recognising the positives, but detailing its key demerits and their deleterious educational, and cultural, influence.

There are many informative accounts of Kuhn’s personal, educational, and academic life.10 And, of course, there are many more accounts of his achievements, real and contested. Separating Kuhn’s real from his imagined achievements has, for 60 years, engaged legions of scholars.11 In 2012, the 50-year anniversary of publication of Structure was marked by numerous celebratory conferences in many countries.12 A large international centenary conference celebration of Kuhn’s life and work, held in July 2022, is witness to his enduring interest among historians, philosophers, and other scholars.13

Kuhn’s philosophy, his account of the nature of science, and the conditions for, and mechanisms of, theory change in science have been exhaustively appraised by historians and philosophers.14 Richard Duschl and Richard Grandy are of the opinion:

The most recent movements in philosophy of science can be seen as filling in some of the gaps left by Kuhn’s demolition of the basic tenets of logical positivism. (Duschl & Grandy, 2008, p.8)

This is an orthodox, majority account of Kuhn’s influence. And it is generous. An alternative reading would be to describe recent movements as ‘correcting mistakes in’ or ‘clarifying ambiguity about’, rather than ‘filling in gaps’, and further, pointing to how much he, and more generally Kuhnians, shared, rather than demolished, some of the basic tenets of logical positivism.15

Different Structures: Ernest Nagel’s Structure (1961) and Thomas Kuhn’s Structure (1962)

In successive years, two HPS books part-titled Structure were published. Ernest Nagel’s (1901–1985) 600 + page The Structure of Science: Problems in the Logic of Scientific Explanation was published in 1961 (Nagel, 1961). Kuhn’s 170 + page The Structure of Scientific Revolutions was published in 1962. Beginning with his choice of title, Kuhn took aim at Nagel’s book and largely displaced it from academic discussion. Kuhn’s Structure opened a new chapter in the history of HPS. It sold a million-plus copies in at least 18 languages; Nagel’s sold the smallest fraction of that in a handful of languages. Kuhn sold to the masses and Nagel to captive philosophy students, including the current author. The Nagel/Kuhn contrast is an informative background for the arguments of this paper.

Nagel’s was a widely adopted philosophy text giving a detailed exposition of the logical empiricist ‘picture’ of science. This encapsulated the dominant philosophical, cultural, and educational understanding of science of the era.16 The book was the received view’s manual. Its Preface encapsulates post-war, progressive society’s hopes for science. Nagel speaks of science as an ‘institutionalized art of inquiry’ that has yielded precious fruit. Foremost among these are:

The achievement of generalized theoretical knowledge concerning fundamental determining conditions for the occurrence of various types of events and processes; the emancipation of men’s minds from ancient superstitions in which barbarous practices and oppressive fears are often rooted. (Nagel, 1961, p. vii)

He proceeds down a long list of social and cultural achievements, concluding:

Despite the brevity of this partial list, it suffices to make evident how much the scientific enterprise has contributed to the articulation as well as the realization of aspirations generally associated with the idea of a liberal civilization. (ibid)

This was a restatement of core Enlightenment convictions. The book was to be the first of three volumes laying out Nagel’s philosophical reflections on science.17 He rightly observed that: ‘there are few notable figures in the history of Western philosophy who have not given serious thought to problems raised by the sciences of their day’ (Nagel, 1961, p. viii).18 He recognises there are many problems occasioned by science that warrant philosophical attention, but:

… the present book is controlled by the objective of analyzing the logic of scientific inquiry and the logical structure of its intellectual products. (Nagel, 1961, p.viii)

Nagel’s Structure had a very low profile, if any, in science education. However, the discipline enthusiastically embraced Thomas Kuhn, especially after publication of the 1970s edition of Structure. But, as shown in the following sections, Kuhnianism was more embraced than appraised by educators. This indicates a fundamental deficiency in the discipline: The failure to incorporate history and philosophy of science into teacher education or graduate programmes.

Unheralded Birth of Kuhn’s Structure

The first edition of Structure appeared in 1962 in the Vienna Circle-inspired, International Encyclopedia of Unified Science (Volume 2 Number 2). It had been founded by Otto Neurath and subsequently edited in the USA by Rudolf Carnap and Charles Morris. The Encyclopedia was the post-war flagship of logical empiricism; it had an almost entirely philosophical readership. The first edition was hardly noticed outside of philosophy departments, and not at all outside the academy.

An exception to the general neglect was a famed panel discussion titled ‘Criticism and the Growth of Knowledge’ at the July 1965, London International Colloquium for the Philosophy of Science. The contributors were Thomas Kuhn, John Watkins, Stephen Toulmin, L. Pearce Williams, Karl Popper, Margaret Masterman, Imre Lakatos, and Paul Feyerabend. This was a sort of ‘HPS fights back’ event. The papers were published as a book in 1970, and enjoyed huge sales, becoming a basic text in upper-level philosophy of science courses (Lakatos & Musgrave, 1970). It was published the same year as the second edition of Structure.

The first edition was not noticed by science educators. John Robinson’s The Nature of Science and Science Teaching (Robinson, 1968) was the first book whose title brought together philosophy of science and science teaching. Kuhn is nowhere mentioned in its 150 pages (Matthews, 1997). In 1968, there was an important panel discussion on ‘Philosophy of Science and Science Teaching’ at the annual US National Association for Research in Science Teaching conference. Contributors included John Robinson, Michael Connelly, and Marshall Herron. The papers were published the following year in Volume Six of The Journal of Research in Science Teaching. Kuhn is not mentioned.

In 1969, Hans O. Andersen published Readings in Science Education for the Secondary School (Andersen, 1969). It was a collection of 60 research papers informed by commitment to the principle:

Science instruction should be based on a series of principles selected for their value in projecting science as a process of inquiry designed to discover new facts, improve quantitative descriptions of known facts, and organize these facts into conceptual schemes which more adequately describe the phenomena of the universe and beyond. (Andersen, 1969, p.2)

And:

The only way to succeed in increasing science enrolments without a subsequent loss of positive attitude is to make the course offerings so interesting and so valuable to the student that he will demand more. (Andersen, 1969, p.2)

Kuhn does not appear in the anthology’s 430 pages, and 60 readings. In 1974, Michael Connelly commented of the post-Sputnik curricular boom that:

While this activity began with philosophical concerns for knowledge and for enquiry, it was largely dominated by the works of a few psychologists, notably, Bruner, Ausubel, Gagne, Piaget. (Abimbola, 1983, p.182)

A few rare commentators in the 1960s, who were familiar with both the philosophical and the educational literature, noted this neglect of ‘new’ philosophy by science educators. Yehuda Elkana (1934–2012) observed that science education during the 1950s, and leading up to the Sputnik era, was formed in the image of ‘inductivist-realist’ philosophy of science (Elkana, 1970, p.3). He said of post-Sputnik PSSC and BSCS curricula and teaching material, that they ‘reflect the positivistic-Instrumentalist philosophy of science [logical empiricism], which was at the height of its influence in the early days of space travel’ (Elkana, 1970, p.8).

Elkana lamented that two important books—Kuhn’s Structure and Joseph Schwab’s The Teaching of Science (Schwab, 1960)—were published at the same time yet shared no common literature. They were: ‘two very important books, both highly influential in their own fields, both relying on two traditions and two bibliographies which completely ignore each other’ (Elkana, 1970, p.15). Elkana sketched out the ‘practical implications for the teaching of science’ that Kuhn’s new philosophy of science generated.

Michael Martin (1932–2015), a Boston University philosopher, a few years later surveyed the same literature as Elkana. He paid particular attention to the rush of ‘inquiry’ and ‘discovery’ curricula and recommendations put into Western educational orbit by Sputnik. Martin drew attention to the important 1966 Educational Policies Commission report, Education and the Spirit of Science (EPC, 1966), and charted the myriad ways in which it, and other curricula as well, reproduced simplistic, mistaken, inductivist understanding of scientific inquiry (Martin, 1972, 141–147). The homely inductivism of Education and the Spirit of Science had the imprimatur of the highest office in US education.

Much had happened in HPS in the decade leading up to the EPC report. It was published eight years after Norwood Russell Hanson’s Patterns of Discovery (Hanson, 1958) which received wide philosophical attention for its ‘theory dependence of observation’ thesis; seven years after Popper’s anti-inductivist work The Logic of Scientific Discovery (Popper, 1934/1959) was translated into English and also given wide philosophical attention; and four years after the publication of Feyerabend’s essay ‘Explanation, Reduction, and Empiricism’ that shook the foundations of inductivist accounts of science (Feyerabend, 1962). Science educators, especially those at the highest levels advising Federal Government curricular and education-funding bodies, should have had an inkling of the shifting ground in HPS and should have recognised its relevance to its report on the ‘Spirit of Science’.

In 1974, Martin opined:

a great deal has been written on the philosophy of science; perhaps even more has been written in science education. However, surprisingly little has been written on the relation between the two areas. (Martin, 1974, 293)

The era’s unfortunate divide between HPS and science education was well documented in a study by Richard Duschl titled ‘Science Education and Philosophy of Science: Twenty-five Years of Mutually Exclusive Development’ (Duschl, 1985).19

Embrace of the Second Edition

The second edition (1970), unchanged except for addition of a Postscript,20 took Kuhn to the world. Kuhn was enthusiastically taken into education and into nigh on all other academic disciplines. In 1985, Derek Hodson reported that of 22 research articles published, and theses submitted, in the field of ‘Philosophy of Science, Science and Science Education’, in the period 1974–1984, fourteen addressed Kuhnian themes (Hodson, 1985).

In 2000, Cathleen Loving and William Cobern conducted a citation analysis of two major science education journals—Science Education and Journal of Research in Science Teaching—for the 13-year period 1985–1998 and, not surprisingly, found that there were numerous citations of Kuhn covering such Kuhnian themes as: paradigms (30 articles), conceptual change theory (12 articles), constructivist epistemology, incommensurability, authenticity of textbooks, the social components of science, and also the philosophical comparison of Kuhn and other methodologists of science (Loving & Cobern, 2000).

Clearly, there were many Kuhn enthusiasts in the science education community. It was close to being a Kuhnian cheer-squad (Matthews 2004a).

The embrace of Kuhn is demonstrated in one of the first science education articles to engage with Kuhn’s theory, namely, Ted Cawthron and Jack Rowell’s ‘Epistemology and Science Education’ (Cawthron & Rowell, 1978). They drew parallels between Piaget’s theory of knowledge and his psychological account of the constructive knowing subject, and what they found in Kuhn. For them, Kuhn established that:

We see things not just as they are but also partly as we are, and this is not due simply to differences in interpretation of otherwise stable facts or data. The “objective” real world becomes merged with its “subjective” interpretation and the Cartesian Dichotomy is replaced by a dialectic epistemology with distinctly relativistic implications. (Cawthron & Rowell, 1978, p.45)

What they are identifying as Kuhn’s ‘dialectic epistemology with distinctly relativistic implications’ is Kuhn’s embryonic and unsophisticated, Kantianism, something he picked up in a Harvard General Education course.

Structure: An Outline

As it was Kuhn’s Structure, and almost Structure alone, that impacted science education, that book will be the focus of this paper’s argument. More particularly, the book’s anti-realist and incommensurability claims will be examined as these had the most enduring impact in science education. They are still, for example, centre stage in important debates in Canada, Australia, New Zealand, and elsewhere, about whether indigenous science should be included in a science programme or a social science programme.21

Key elements of Structure can be seen in Kuhn’s, 1951 Lowell Lectures delivered in the Boston Public Library—The Quest for Physical Theory. These ‘adult education’ or ‘university outreach’ lectures remained unpublished until 2021 when they were edited by George Reisch and published by the MIT Library (Kuhn, 1951/2021). In criticism of Karl Pearson’s popular empiricist account of science which embodied the ‘orthodox’ logical empiricist view of the time (Pearson, 1892/1937), Kuhn averred:

I should like to suggest that the impartial, dispassionate observation of nature is impossible, that there are no “pure facts” from which alone valid theories can be derived, and that the effort toward “self elimination” which Pearson proposes as the scientist’s goal, would, in practice, result in the abolition of productive research. (Kuhn, 1951/2021, p.3)

The core argument of Structure is well known and could be summarised as follows.22 All communities seek knowledge and understanding of nature. This can amount to pre-science, pseudoscience, protoscience, or science. Normal science is heralded by the appearance of a common paradigm, or exemplar, that dictates methods of inquiry and constrains the kind of entities, or ontology, that can be appealed to in scientific explanations. The paradigm provides theoretical and practical puzzles that scientists work away at solving. When some pressing practical or theoretical puzzles resist solution with tools and concepts provided by the paradigm, then science enters a crisis period, and either drastic renovation is done (maybe new rooms added or boarders taken in) or scientists embrace a new paradigm (move house). This is revolutionary science. Crucially, while decisions within a paradigm are rule regulated, as evidenced in processes of journal review, decisions about how extensive a renovation should be—whether a particular addition is permissible, or whether to pick up and move house—are not rule regulated.

For Kuhn, values and interests, including personal ones, determine those decisions; they are an unavoidable part of science; and values are embedded within paradigms. Productive paradigms, and theories within them, unavoidably embody standards (values) of accuracy, consistency, breadth, simplicity, and fruitfulness. These are qualities that scientists, with good reason, prefer for their theories (McMullin 2008). And these values are common across paradigms, even incommensurable ones. As Kuhn later elaborates:

such values as accuracy, scope, and fruitfulness are permanent attributes of science …. (Kuhn, 1977b, p.335)

But he advises that:

the relative weights attached to them have varied markedly with time and also with the field of application. (Kuhn, 1977b, p.335)

So subjectivity is built into science.

Purple Passages

In the first edition, and remaining unchanged in the second, there were many ‘purple passages’ as Kuhn later labelled them (Kuhn, 1970a). These were head-turning claims that threatened the orthodox logical empiricist, and widespread cultural, understanding of science, understandings that were codified by Nagel:

‘…once current views of nature were, as a whole, neither less scientific nor more the product of human idiosyncrasy, than those current today’ (p.2).

viewing all fields together science ‘is a rather ramshackle structure with little coherence between its various parts’ (p.49).

‘Like the choice between competing political institutions, that between competing paradigms proves to be a choice between incompatible modes of community life’ (p.94).

‘What occurred [when paradigms changed] was neither a decline nor a raising of standards, but simply a change demanded by the adoption of a new paradigm’ and ‘it could be reversed’ (p.108).

‘I have so far argued that paradigms are constitutive of science. Now I wish to display a sense in which they are constitutive of nature as well’ (p.110).

‘after discovering oxygen Lavoisier worked in a different world’ (p.118).

transition to a new paradigm occurs ‘not by deliberation and interpretation, but by a relatively sudden and unstructured event like a gestalt switch’ (p.122).

‘the competition between paradigms is not the sort of battle that can be resolved by proofs’ (p.148), and … ‘in these matters neither proof nor error is at issue’.

‘the proponents of different paradigms practice their trades in different worlds … the two groups of scientists see different things when they look from the same point in the same direction’ (p.150).

‘The transfer of allegiance from paradigm to paradigm is a conversion experience that cannot be forced’ (p.151).

‘a man who embraces a new paradigm at an early stage must often do so in defiance of the evidence provided by problem solving. … A decision of that kind can only be made on faith’ (p.158).

‘the phrases “scientific progress” and even “scientific objectivity” may come to seem in part redundant’ (p.162).

‘with respect to normal science … progress lies simply in the eye of the beholder’ (p.163).

‘we may have to relinquish the notion, explicit or implicit, that changes of paradigm carry scientists and those who learn from them closer and closer to the truth’ (p.170).

And so on and on.

Kuhn would later regret writing some of these passages, but he held on to others. In 1969, he wrote: ‘I now recognize aspects of its initial formulation that create gratuitous difficulties and misunderstandings’ (Kuhn, 1970a, p.174). Steven Shapin generously called such passages ‘Kuhn’s sound-bites’ (Shapin, 2015, p.11). He could equally have called them ‘ill thought out’, ‘careless’, or ‘irresponsible’ claims. In 1969, in the Postscript to Structure, Kuhn wrote ‘I now recognize aspects of its initial formulation that create gratuitous difficulties and misunderstandings’ (Kuhn, 1970a, p.174). A year later, in distancing himself from charges of ‘irrationality’, ‘mob rule’, and ‘relativism’, with which he had rightly been charged, Kuhn admitted that his ‘own past rhetoric is doubtless partially responsible’ (Kuhn, 1970b, p.260).

Kuhn does not regret his lack of training in philosophy; on the contrary, he thought the lack advantageous as it did not give him a certain, but not spelt out, philosophers’ ‘cast of mind’. But if the above passages had been written into a graduate, or even undergraduate, philosophy thesis in most decent programmes, they would have been struck out: ‘this work cannot be presented, take it away and clarify’. Such guidance in 1960 would have made a seismic difference to subsequent philosophical and cultural thought.

Anticipations of Structure

The central philosophical ideas in Structure were not novel, something Kuhn often acknowledged.23 Many elements of his philosophy of science were extant; indeed, many elements were in residence just along the Harvard corridors. But these were barely, if at all, acknowledged, much less engaged with when the first edition of Structure was published in 1962. The intellectual ground for the Kuhnian ‘revolution’ had been well prepared. Simple empiricist, individualist, logical positivist understandings of science—the knower confronting the world—had been challenged on many fronts; the time was ripe for a philosophical upheaval, if not revolution.24

Marx’s 1852 Eighteenth Brumaire of Louis Bonaparte could have been, and by a few was, appealed to by opponents of the orthodox empiricist account of science. Marx memorably wrote:

Men make their own history, but they do not make it just as they please … they make it under circumstances directly found, given and transmitted from the past. The tradition of all the dead generations weighs like a nightmare on the brain of the living. (Tucker, 1978, p.595)

This is an early statement of the sociology of knowledge, and was acknowledged as such by Karl Mannheim, the founder of that discipline (Mannheim, 1936/1960). It denies all ‘Robinson Crusoe’, individualist, observer-confronts-the-world epistemologies. It lays out how the ‘we think’ determines, or at least constrains, the ‘I think’. Marx’s observation was consistent with Kuhn’s epistemological programme and might be reformulated as ‘the paradigms of all the dead generations weighs like ….’.

In the 1930s, Ludwik Fleck wrote on the social construction of facts and on the necessity of an historical component for understanding (Fleck, 1935/1979, Cohen & Schnelle, 1986). At the same time, Gaston Bachelard wrote on epistemological ruptures in the history of science and on the impact of epistemological obstacles on cognition (Bachelard, 1934/1984).

In the 1930s and 1940s, Alexandre Koyré extensively documented the centrality of metaphysics in the science of Galileo and Newton (Koyré, 1957, 1968). In the 1940s, R.G. Collingwood elaborated how particular periods in the history of science had different metaphysical presuppositions which were fundamental assumptions about the constituents of the world and their properties that were not given directly in experience (Collingwood, 1940, 1945).

James Conant (1893–1978), while President of Harvard and the director of Kuhn’s own General Education course, had written popular books pointing to ‘conceptual schemes’ as the skeleton of science, and their transformation as the consequence of ‘scientific tactics and strategy’ (Conant, 1947, pp.104–111). Kuhn, with enthusiasm and gratitude, embraced Conant’s ‘conceptual schemes’ as a means to elucidate the nature of science and its history (Wray, 2016).25

Philipp Frank (1884–1966), a Harvard physics professor and a major exponent of logical empiricism, had been since the 1930s publishing accounts of science that shared a great deal with Kuhnian views. In the opening chapter of his The Law of Causality and its Limits (1932), he observes:

The more a physicist or biologist refuses to concern himself with ‘philosophy’, respectfully or contemptuously, the more we can be sure that he adopts the views of the oldest traditional scholastic philosophy in good faith, because he has not given careful thought to the fundamental concepts of his science. In the elementary textbooks of purely experimental physics, the most astonishing metaphysical claims can be found. (Frank, 1932/1998, p.25)

This is a constant theme in his work. In the Preface to his Philosophy of Science, he says ‘the deeper we dig into actual science the more its links with philosophy become obvious’ (Frank, 1957, p.iv). Further, he is well aware of the need for concrete historically based analysis, warning that:

Presentations of this field have very often started from a concept of science that is half vulgar and half mystical. Other presentations have linked science with a philosophy that has actually been a mere system of logical symbols without contact with historical systems of philosophy. (Frank, 1957, p.iv)

The ‘historical turn’ in philosophy of science did not have to await the Kuhnian revolution. Consequently, Frank’s Philosophy of Science contains analyses of the scientific and philosophical contributions of Aristotle, Bacon, Copernicus, Descartes, Einstein, Foucault, and pretty much down the rest of the alphabet to Whewell and Young. In all of his writing, Frank stresses the importance of extant conceptual frameworks for science and relentlessly examines grounds for choosing frameworks and for changing frameworks. Herbert Feigl provides an accurate summary of Frank’s philosophical orientation, saying that it:

combines informal logical analysis of the sciences with a vivid awareness of the psychological and socio-cultural factors operating in the selection of problems, and in the acceptance or rejection of hypotheses, and which contribute to the shaping of styles of scientific theorizing. In a sense this is a genuine sequel to the work of Ernst Mach. (Feigl, 1956, pp.4-5)

All of this was grist for the Kuhnian mill, but Frank’s name appears in Structure only as the biographer of Einstein. Kuhn’s failure to engage with the work of such an eminent Harvard colleague is the more surprising as Frank had explicitly written on education. In 1947, he published an article in the American Journal of Physics titled: ‘The Place of Philosophy of Science in the Curriculum of the Physics Student’ (Frank, 1947/2004).

Gerald Holton, a Harvard colleague and fellow contributor to the General Education programme, had in the 1950s written on the role of organising principles, or ‘themata’, in science (Holton, 1952/1984, 1973/1988).26 Holton acknowledges Frank as the person who opened his eyes to the intimate connection of physics with philosophy:

… the interaction between science and epistemology was at the center of attention in discussions over many years with Philipp Frank, that most humanistic and conciliatory of logical empiricists, and biographer of Albert Einstein. (Holton, 1973, p.25)

Holton’s Thematic Origins of Scientific Thought (Holton, 1952/1984) was published in 1952, eight years before the first edition of Structure, but is not mentioned in either the first or second edition. Had Kuhn made clear the commonalities and differences between his paradigms (or disciplinary matrices, as he would relabel them in the 1970 ‘Postscript’)27

In response to criticisms of his notion of paradigm, Kuhn changed terminology to ‘disciplinary matrix’. A matrix had four components: symbolic mathematised generalisations and formulae; metaphysical interpretations of basic models and analogies; epistemic and non-epistemic values shared by all practitioners; and exemplars showing productive puzzle generation and solutions (Kuhn, 1970a, pp.182–187). These have obvious connections to Holton’s themata. Science education would have gained if educators had paid as much attention to Thematic Origins as they did to Structure.28

Willard van Orman Quine (1908–2000), Harvard’s most eminent philosopher, in 1951 published his famed ‘Two Dogmas of Empiricism’ (Quine, 1951). His argument was widely acknowledged to have dissolved the analytic/synthetic distinction so fundamental to the empiricist tradition with which Kuhn was battling. For Quine, theoretical statements never confront experience or experiment in isolation, but always as part of a constellation including methodological and metaphysical commitments, and where adjustments can be made elsewhere to reconcile theory and observation.Beliefs were not isolated; they were always part of a web.29

Hilary Putnam (1926–2016), yet another distinguished Harvard colleague, recognised Kuhn as ‘one of the most ingenious contemporary philosophers and historians of science’ (Putnam, 1990, p.123). In 1962, Putnam, in a much-cited paper, engaged with, and criticised, Quine’s supposed dissolution of the analytic/synthetic distinction. In doing so, he wrote:

It has been necessary to consider problems connected with physical science (particularly the definition of ‘kinetic energy’, and the conceptual problems connected with geometry) in order to bring out the features of the analytic-synthetic distinction that seem to me to be the most important. (Putnam, 1962, p.358)

In defending analyticity as a genuine, realistic, and informative category in the science of energy, Putnam gives, in the publication year of Structure, an almost mirror account of a Kuhnian paradigm without using the word:

If a physicist makes a calculation and gets an empirically wrong answer, he does not suspect that the mathematical principles used in the calculation may have been wrong (assuming that those principles are themselves theorems of mathematics) nor does he suspect that the law ‘F = ma’ may be wrong. Similarly, he did not frequently suspect before Einstein that the law ‘E = 1/2mv2’ might be wrong or that the Newtonian gravitational laws might be wrong (Newton himself did, however, suspect the latter). These statements, then, have a kind of preferred status. They can be over-thrown only if someone incorporates principles incompatible with those statements in a successful conceptual system. (Putnam, 1962, pp.371-372)

Putnam and Kuhn, though in the same Harvard ‘corridor’, did not, in print, publicly engage. This is more than peculiar as one of Kuhn’s most substantial historical studies was his ‘Law of Energy Conservation’ (Kuhn, 1959b). Kuhn saw himself as a philosopher and, outside Harvard, was widely seen to be one. But in writing Structure, he engaged very little with the arguments and analyses of the top-flight philosophers who were literally all around him. Putnam is not even in the index of The Essential Tension which was Kuhn’s selection of his own HPS studies (Kuhn, 1977b), and he does not appear in the collection of Kuhn’s 1970–1993 philosophical essays (Conant & Haugeland, 2000).

The foregoing amounted to Kuhn’s missed local opportunities for philosophical engagement.30 But sympathetic philosophers had been writing in many other places on topics germane to Structure. Stephen Toulmin (1922–2009) wrote on how discoveries in the physical sciences consisted, in part, of finding fresh ways of looking at phenomena, and advocated the importance of history when doing philosophy of science (Toulmin, 1953). A little later, Norwood Russell Hanson (1927–1964) famously wrote on the theory dependence of observation and on the contested nature of the facts in scientific disputes (Hanson, 1958). In Hanson’s work, two of the foundations of logical empiricism were cut adrift. Ludwig Wittgenstein had made philosophers attentive to the distinctions between seeing and seeing as; between looking and noticing; and between object perception and propositional perception. The last requires language and judgement and hence varying degrees of theory (Wittgenstein, 1958).

Michael Polanyi (1891–1976), in his book Personal Knowledge (Polanyi, 1958) and elsewhere, wrote on the place of tacit, assumed, ‘subterranean’ knowledge in science; the corrective function of the scientific community; and the importance of initiation into accepted methodologies and practices for the conduct of science. In 1961, in a conference commentary on a pre-Structure paper of Kuhn’s, Polanyi wrote:

A commitment to a paradigm has thus a function hardly distinguishable from that which I have ascribed (Polyani, 1958, chaps.5,6,7) to a heuristic vision, to a scientific belief, or a scientific conviction. (Polyani, 1963, p.375)

Rom Harré (1927–2019) in the early 1960s wrote on the centrality and necessity of general conceptual schemes in science, their impacts, how they were modified, and on the ubiquity of metaphor and metaphysic in science (Harré, 1960, 1964). He recognised, as most did, that:

Empirical investigations do not exhaust the kinds of question raised by a conceptual crisis. There are also questions of a more metaphysical kind. Empirical investigations are not immediately relevant to these, nor do empirical facts provide conclusive answers. (Harré, 1964, p.65)

Max Black (1909–1988) had written extensively on the role of metaphor and analogy in scientific thinking and had rejected the notion of language as a mirror of nature (Black, 1962). Mary Hesse (1924–2016), a historically informed philosopher, argued in different publications that in neither science nor history of science are there ‘bare uninterpreted facts; all facts, whether experimental or historical, are interpreted in the light of some theory’ (Hesse, 1961 p.v).

Kuhn’s failure to engage with Rudolf Carnap’s (1891–1970) philosophy is especially noteworthy.31 In the mid-late 1950s, while Kuhn was teaching in the General Education Programme and when Structure was being penned, Carnap was at the height of his powers and academic standing (Schilpp, 1963). He was a doyen of logical empiricism, the ‘system’ that Kuhn’s work was consciously directed against. He was co-editor of the Encyclopedia of Unified Science that commissioned Kuhn’s Structure essay. In that editor’s capacity, Carnap wrote to Kuhn in 1960 and again in 1962 commending the manuscript, and saying in 1962 when accepting the manuscript for publication, that:

In my own work on inductive logic in recent years I have come to a similar idea: that my work and that of a few friends in the step for step solution of problems should not be regarded as leading to “the ideal system”, but rather as a step for step improvement of an instrument. (Reisch, 1991, p.267)

And Carnap addressed in 1963 (originally in German in 1935) ‘revolutionary’ change in science when theories finally cannot be reconciled with observation. He writes that the scientist has two options:

a change in the language, and a mere change in or addition of, a truth-value ascribed to an indeterminate statement.... A change of the first kind constitutes a radical alteration, sometimes a revolution, and it occurs only at certain historically decisive points in the development of science. (Reisch, 1991, p.270)

Michael Friedman, in his article ‘Kant, Kuhn and the Rationality of Science’, wrote on the unexpected comparability of Carnap’s and Kuhn’s account of science:

Thus Kuhn’s central distinction between change of paradigm or revolutionary science, on the one side, and normal science, on the other, closely parallels the Carnapian distinction between change of language or linguistic framework and rule-governed operations carried out within such a framework. (Friedman, 2002, p.181)

John Earman, writing as ‘a distant student of Carnap and a close student of Kuhn’ (Earman, 1993, p.32), says:

Although I am no apologist for logical positivism, it does seem to me that many of the themes of the so-called postpositivist philosophy of science are extensions of ideas found in the writings of Carnap and other leading logical positivists and logical empiricists. (Earman, 1993, p.9)

For Carnap, the choice of a particular linguistic framework is not driven by rules; but moves within the framework are so driven or governed. This is close to Kuhn’s choosing between paradigms, and working within paradigms. But for science, nature comes into the picture. Here was common ground that could have been explored with Kuhn’s own academic sponsor, but this did not happen.32

In Kuhn’s biographical interview, he confesses that he:

read a little bit of Carnap, but not the Carnap that people later point to as the stuff that has real parallels to me. … I have confessed to a good deal of embarrassment about the fact that I didn’t know it. (Baltas et al., 1997/2000, p.305-306)

Disarmingly, he proceeds to say:

On the other hand, it is also the case that if I’d known about it, if I’d been into that literature at that level, I probably would never have written Structure. (Baltas et al., 1997/2000, p.306)

This is likely a true conjecture, and what a momentous one it is: The post-1960 scholarly and cultural worlds would be very different if Kuhn had spent his time reading, understanding, and engaging with Carnap, and other extant literature, rather than writing Structure. His decision to write rather than read had a butterfly effect. An avalanche of publications and book sales followed upon the decision. Other physicists did do the ‘hard yards’ in philosophy and so they better served the long-term philosophical and educational purposes that Kuhn himself sought to serve, though they did not have his sales or citation figures.33

In brief, by 1960, much had been written on the intellectual complexity of science, on the challenging junction of science and metaphysics,34 and on the ‘embeddedness’ of science in society and culture. Much of this had been written on under the heading of ‘Internal versus External History of Science’ (Basalla, 1968). A good deal of these noteworthy elements of Structure had been written about by Kuhn’s own Harvard colleagues—Frank, Conant, Quine, Scheffler, Putnam, and Holton. In the first edition (1962), Kuhn recognised few of these antecedents and engaged with only a subset of those. There was some engagement in the Postscript of the second edition (1970), but not much. Engagement with philosophers picked up in his subsequent philosophical writing,35 but only the smallest proportion of the million-plus readers of Structure read his later essays.

Alexander Bird, in his biography of Kuhn, gives an accurate, but understated, account of the degree to which Kuhn’s positions had already been voiced:

There are the seeds of Kuhn’s own revolution in such historians and sociologists as Ludwick Fleck, Karl Mannheim and Robert Merton, as well as philosophers such as Toulmin and Hanson. (Bird, 2000, p.2)

To Kuhn’s credit, his Structure brought all these contra-empiricist elements together within a seemingly coherent narrative that could be easily read, though not always understood, by many.

A good deal of what educators found attractive and engaging in Structure was out there and public in earlier books by other philosophers and historians. Unfortunately, there was no tradition, or expectation, that science educators, teachers, or students would read and engage with such literature. Philosophy, or HPS more specifically, was not part of teacher education or seen to be an essential part of a science teacher’s professional responsibility. And HPS was not an expected part of an education-researcher’s repertoire.

Interpreting Kuhn

Before appraising the claims and arguments of an author, the first task is the exegetical one of laying out just what are the author’s claims and then determining if they are consistent over time or change with maturation and criticism. For Kuhn, exegesis is uncommonly difficult. He was not a disciplined writer, or at least not as disciplined as his subject matter—the history, processes, methods, and achievements of science—deserved. In a delightfully revealing and lengthy 1995 interview conducted in Athens less than a year before his death, Kuhn relates how he attended an undergraduate seminar at Princeton where, in response to audience enthusiasm for ‘Kuhnian’ ideas, he objected:

I kept saying ‘But I didn’t say that! But I didn’t say that! But I didn’t say that! (Baltas et al., 1997/2000, p.308)

In his 1991 Rothschild Harvard lecture—‘The Trouble with the Historical Philosophy of Science’—he said of the hugely popular Edinburgh-based sociology of scientific knowledge programme36 that it:

Frequently troubles me, not least because it was initially emphasized and developed by people who often called themselves Kuhnians. I think their viewpoint damagingly mistaken, have been pained to be associated with it, and have for years attributed that association to misunderstanding. (Kuhn, 1991/2000, p.106)

This refrain of ‘I did not say that’, or ‘you have misunderstood me’ is common. Kuhn does not pause to reflect on why senior scholars such as David Bloor, Harry Collins, Trevor Pinch, John Henry, and Barry Barnes, to say nothing of multiple hundreds of thousands, if not millions, of lesser scholars and students, could misunderstand what he wrote. He attributes this to their lazy reading, not to his careless writing. Slow, tedious, sometimes page-by-page exegesis is a bugbear, but a necessary one in analysis of Kuhn and Kuhnian argument. Philosophers resented having to do this; they expected clearer, less ambiguous writing.

The deficiency of Kuhn’s ‘soft-focus’, or undisciplined, writing was shown in an early review of Structure. Dudley Shapere, who acknowledged the ‘vast amount of positive value in Kuhn’s book’, focused, as so many did, on Kuhn’s introduction of ‘paradigm’. At the very outset paradigm was defined as:

a set of “universally recognized scientific achievements that for a time provide model problems and solutions to a community of practitioners”. (Kuhn, 1962/1970 p. viii)

Shapere went on to argue that Kuhn’s truly revolutionary account of theory changes in the history of science:

… is made to appear convincing only by inflating the definition of ‘paradigm’ until that term becomes so vague and ambiguous that it cannot easily be withheld, so general that it cannot easily be applied, so mysterious that it cannot help explain, and so misleading that it is a positive hindrance to the understanding of some central aspects of science; and then, finally, these excesses must be counterbalanced by qualifications that simply contradict them. (Shapere, 1964, p.393)

None of these considerations prevented ‘paradigm’ appearing, like Spring blossoms (to use a generous simile), across the scholarly, social, and cultural worlds after Structure’s publication in 1962. For Kuhn, Hume’s ‘slow, lingering method’ of philosophical analysis was alien. It is something that requires schooling, and Kuhn repeatedly acknowledges that he did not have it.

Margaret Masterman, at the important 1965 London conference session on Structure, identified 21, ‘or was it 23’, different meanings of ‘paradigm’ in the book’s first edition (Masterman, 1970). Kuhn was in the conference audience and, thirty years later, commented:

And I sat there, I said, my God, if I had talked for an hour and a half, I might have gotten these all in, or I might not have. But she's got it right! And the thing I particularly remember, and I can't make it work quite but it's very deeply to the point: a paradigm is what you use when the theory isn't there. And she and I interacted then, during the rest of my stay, quite a lot. (Baltas et al., 1997/2000, p.299-300)

Scholars do change, or refine, their positions in response to criticism and upon further reflection. This is commendable and Kuhn did so (Hoyningen-Huen, 2015). In 1993, he wrote:

Whatever I may have believed when I wrote the Copernican Revolution [1957], I would not now assume … ‘that the simpler, the more beautiful [astronomical] models are more likely to be true’. (Kuhn, 1993, p.331)

He changed his mind on this point simply because he gave up altogether on truth as a realisable goal of science.

Abandoning truth was a seismic change. Less seismic was his discarding of ‘paradigm’ which soon enough became a mixture of ‘lexical structure’ plus ‘exemplar’ (Kuhn, 1993, p.326). This construction did not catch on; it did not have the ring of ‘paradigm’ which lived on enjoying a life of its own long after its creator abandoned it. Exegesis details where and when change occurs. Further attention, beyond exegesis, might reveal why the change occurs, and whether it was justified.

Philosophers on Kuhn

Philosophers did not entirely ignore the first edition of Structure. Most notably, and publicly, Paul Feyerabend, Imre Lakatos, Margaret Masterman, Stephen Toulmin, and Karl Popper engaged with it at the 1965 London Philosophy of Science Congress (Lakatos & Musgrave, 1970). Many other philosophers, including those mentioned below, rose to the Kuhnian challenge.

John Searle, a philosopher, points to the need for externalist, sociological, or naturalist, rather than internalist, epistemic explanations for the embrace of Kuhnianism:

… the remarkable interest in the work of Thomas Kuhn on the part of literary critics did not derive from a sudden passion in English departments to understand the transition from Newtonian Mechanics to Relativity Theory. Rather, Kuhn was seen as discrediting the idea that there is any such [objective] reality. If all of ‘reality’ is just a text anyway, then the role of the textual specialist, the literary critic, is totally transformed. (Searle, 1994, p.38)

Kuhn’s ‘novel’ ideas were taken out of the philosophy corridor and broadcast in the marketplace. The Kuhnian wave broke over philosophy departments, and in quick succession of other humanities, social science, and education departments. There have been many substantial monographs and collections on Kuhn’s real and imagined philosophy.37

Kuhn cites just a handful of philosophers in the first edition: Wittgenstein, Braithwaite, Polanyi, Whewell, Popper, Goodman, Quine, Nagel, and Hanson. And these, with the notable exception of Hanson, are mentioned only in passing. Kuhn regarded Structure primarily as a contribution to philosophy. Yet only 10% of its sources are philosophical.38 There is no prolonged analysis or evaluation of any philosophical argument, excepting a three-page analysis of arguments about perception, and what contributions the observer makes to the object as perceived.

In Structure, what philosophical arguments there were amounted to empiricism in new clothes: Theory dependence of observation still took observation as fundamental for a theory of knowledge. But debate about the theory dependence, or otherwise, of observation was just an in-house empiricist family-squabble; it occurred within an empiricist ‘paradigm’, as some would say, or within an empiricist ‘problematic’ as others might say. Wallis Suchting (1931–1997) commented:

The central deficiency of empiricism is one that it shares with a wide variety of other positions, namely, all those that see objects themselves, however they are conceived, as having epistemic significance in themselves, as inherently determining the ‘form’, as it were, of their own representation. (Suchting, 1995, p.13)

Mario Bunge (1919–2020), a physicist and philosopher who published significant work in both fields (Matthews, 2019c), recounts in his autobiography that in 1966 he attended an influential colloquium on causality convened in Geneva by Jean Piaget. Kuhn, an admirer of Piaget, was a participant. Bunge observed:

Kuhn’s presentation impressed no one at the meeting, and it confirmed my impression that his history of science was second-hand, his philosophy confused and backward, and his sociology of science non-existent. (Bunge, 2016, p.181)

This is a harsh judgement, but it was made in 1966 after the first edition of Structure (1962), but before publication of the second edition’s Postscript (1970) and Kuhn’s ‘Response to My Critics’ in the Criticism and the Growth of Knowledge collection (Lakatos & Musgrave, 1970). At the time, Kuhn’s most widely known historical work was his book The Copernican Revolution (Kuhn, 1957). He acknowledged that this was entirely derivative and put together from secondary sources for the benefit of his Harvard General Education classes.39

David Stove (1927–1994), an Australian philosopher, wrote of Kuhn:

his entire philosophy of science is actually an engine for the mass-destruction of all logical expressions … [he] is willing to dissolve even the strongest logical expressions into sociology about what scientist’s regard as decisive arguments. (Stove, 1982, p.33)

Stove maintained that Kuhn’s confusion of sociology with epistemology is the reason why:

Kuhn can, and must, sentence all present and future philosophers of science to the torments of the damned: that is, to reading the sociology of science. (Stove, 1982, p.19)

This seems an ‘over the top’ charge, but, in its mitigation, David Bloor, who recognised Kuhn as his philosophical inspiration, published a piece titled: ‘The Sociology of Reasons: Or Why “Epistemic Factors” are really “Social Factors”’ (Bloor, 1984, 295–324). So logical expressions—‘inconsistent with’, ‘entails’, ‘subset’, ‘contradiction’, etc.—only function as such in as much as people believe them. The validity of an argument depends on people thinking it is valid. The effect of this is to replace logic by psychology; the latter substitutes for the former. A consequence is that the important psychological study of poor and aberrant reasoning cannot be conducted, as correct reasoning cannot be identified independently of convictions. Separating ‘good’ psychology from ‘mob’ psychology is otiose.

Israel Scheffler (1923–2014), who had joint appointments in the Harvard Philosophy and Education departments, responded to the first edition of Structure, arguing that Kuhn’s charge of irrationality in paradigm choice:

fails utterly, for it rests on a confusion. It fails to make the critical distinction between those standards or criteria which are internal to a paradigm, and those by which the paradigm is itself judged. (Scheffler, 1966, p.84).

Jan Golinski, a historian, wrote:

I see Kuhn as having little positive influence on philosophers and almost none (directly) on historians. His most significant influence within science studies was mediated by sociologists, whose reading of his work he specifically repudiated. (Golinski, 2012, p.15)

Alexander Bird concluded a sympathetic appraisal of Kuhn with the qualification:

Kuhn’s treatment of philosophical ideas is neither systematic nor rigorous. He rarely engaged in the stock-in-trade of modern philosophers, the careful and precise analysis of the details of other philosophers’ views, and when he did so the results were not encouraging. (Bird, 2000, p. ix)

Consequently, Bird stated:

Structure is not primarily a philosophy text. Rather it is a work in what I call ‘theoretical history’. (Bird, 2000, p.vii)

Abner Shimony (1928–2015), a Boston University physicist and philosopher with substantial publications in both fields (Myrvold & Christian, 2009), said of the key Kuhnian move of deriving methodological lessons from scientific practice that:

His work deserves censure on this point whatever the answer might turn out to be, just because it treats central problems of methodology elliptically, ambiguously, and without the attention to details that is essential for controlled analysis. (Shimony, 1976, p.582)

The ‘controlled analysis’, to which Shimony refers, is a controlled and competent ‘philosophical’ analysis.40

Wolfgang Stegmüller (1923–1991), an Austrian philosopher, opined that the crux of Kuhn’s theory of science was ‘a bit of musing by a philosophical incompetent’ (Stegmüller, 1976, p.216). This was a harsh judgement, but Kuhn was candid in admitting that he had no training in philosophy and was an ‘amateur’ in the discipline (Kuhn, 1991/2000, p.106). And, to a point, he thought that having no formal training was advantageous. This because as he was not schooled in ‘old thinking’, he did not develop a certain ‘cast of mind’ that characterised academic philosophy. This is a pity, as this cast of mind traditionally espoused clear and coherent writing; the cast was uncomfortable with ‘purple passages’ and endeavoured not to compose them.

Michael Devitt agrees with some of Kuhn’s epistemology concerning theory-ladenness and revolutionary theory change, but does not think such agreement requires abandoning truth, or even abandoning the correspondence theory of truth. He regards Kuhn’s ‘semantic and vaguely ontological doctrines as largely, if not entirely, mistaken’ (Devitt, 1991, p.155). And says later: ‘Constructivism is prima facie absurd, a truly bizarre doctrine’ (Devitt, 2001, p.147). The ‘absurd’ doctrine has traction because:

Constructivists typically vacillate between talk of theories or experience and talk of the world. This vacillation is important to the appeal of their message. For, although it is false that we construct the world by imposing concepts on the world, it is plausible to suppose that we construct theories of the world by imposing concepts on experience of the world. The vacillation helps to make the falsehood seem true. (Devitt, 2001, p.148)

It is noteworthy that Kuhn’s long, and charming, 1997 autobiographical interview with Aristides Baltas, Kostas Gavroglu, and Vasso Kindi is, significantly, titled: ‘A Physicist who became a Historian for Philosophical Purposes’.41 Kuhn relates:

I had made that attempt to investigate going into philosophy immediately after the war when I first came back and got into [Harvard] graduate school and I decided I wasn’t going to go back to fulfill undergraduate philosophy. And in certain respects, I’m extremely glad I didn’t, because I would have been taught things that would have given me a cast of mind which would have, in many ways, helped me as a philosopher, but they’d have made me into a different sort of philosopher. So, I had decided, when I applied to the Society [Harvard Society of Fellows], to do history of science. My notion was, and my application indicated, that there was important philosophy to come out of it; but I needed first to learn more History. (Baltas et al., 1997, p.166)

In the light of the philosophical critiques of the first and second editions of Structure, Kuhn did, in a number of important publications, attempt to ‘walk back’ and refine his claims;42 hence, the accepted differentiation between Kuhn I and Kuhn II, or between Radical Kuhn and Mild Kuhn. For the most part, educators and social scientists did not attend to this walking back; they were not aware it had happened. After the blinding relativist and idealist flash of Structure, few recovered their philosophic vision. Although Kuhn’s walk back was applauded by many philosophers, realists thought that he did not walk back far enough. Kuhn’s reality was still too dependent upon the views of the scientist and scientific community; his ontology remains wedded to subjectivity.

Kuhn did not become a professional philosopher. When he was denied tenure in the Harvard General Education Department, there was no question that the Philosophy Department, in which Rawls, Quine, Putnam, and others were in residence, would give equal standing to someone untrained in philosophy. After Harvard, he went to University of California, Berkeley, and had appointments and teaching duties in both the History and the Philosophy departments. At tenure time, the Acting Chancellor called him into his office, and relayed:

The recommendation for your promotion has now gone all the way through, it’s favourable, and I have it on my desk. There is just one thing. The senior philosophers voted unanimously for your promotion – in History. (Baltas et al., 1997, p.182)

For Kuhn:

I was extraordinarily angry … and very deeply hurt, I mean that’s a hurt that has never altogether gone away. (Baltas et al., 1997, p.182)

Kuhn was deeply hurt, and intellectually troubled, telling interviewers in October 1995, less than a year before his death, that he was an ‘anxious neurotic’. In the same interview, he recognised, perhaps with regret, that ‘I’ve never directed a philosophy graduate student’ (Baltas et al., 2000, p.319). He admitted in 1995 that his treatment of the orthodox philosophical tradition was ‘irresponsible’ (Conant & Haugeland, 2000, p.305). This was not a good admission for someone seeking a position in a philosophy department. And elsewhere he confessed: ‘I should never have written the purple passages.’ He was surprised at their impact:

To my dismay, … my ‘purple passages’ led many readers of Structure to suppose that I was attempting to undermine the cognitive authority of science rather than to suggest a different view of its nature. (Kuhn, 1993, p.314)

And it was not just the ‘purple passages’ that were irresponsible; at many points, he advanced ill-considered philosophical and historical arguments. For example, he dismissed Joseph Priestley as an ‘elderly holdout who had ceased to be a scientist’ (Kuhn, 1970a, p.159). This was an assertion that, unjustifiably, blackened Priestley’s name for the million-plus readers of Structure who themselves who had never, and probably would never, read Priestley.43 Many other philosophers and historians pointed to problems and errors in Kuhn’s account of both normal science and the processes of revolutionary change in science.44

Kuhn’s Reach and Overreach

Kuhn’s impact was felt in nearly all disciplines—economics, sociology, psychology, cultural studies, education, and feminism, for starters—and beyond academia into society and culture.45 But his disciplinary impact was in inverse relation to his training and qualifications; he pressed the right buttons and raised important questions, but he disastrously overreached. From the beginning, his impact on HPS puzzled him and should have puzzled many others.

Kuhn is rightly seen as putting ‘paradigm’ and ‘paradigm change’ into the philosophical and social science vocabulary. The word, and expression, is a commonplace in newspaper opinion pieces, political debates, sports reporting, and much else. Its occurrence in the Google Book Ngram Viewer jumped 26-fold between 1960 and 2020.46 Other now-commonplace words and concepts owe their currency to Kuhn: ‘incommensurability’ is oft heard in political and religious debate, ‘theory dependence’ is ubiquitous in social science, ‘gestalt switch’ is now as common in history of science as it has long been in psychology, ‘conversion experience’ moved out of Evangelical sermons into history of science debates, ‘alternative reality’ is not just part of modern US politics but underpins a great deal of educational debate about the teaching of indigenous science, and many other expressions moved out of their Kuhnian home into wider discourse.

There are significant disciplinary and cultural lessons to be learnt from the phenomenon of Kuhnianism. Kuhn had no training in history, philosophy, or sociology; he modestly described himself as an amateur in all three fields. As related in his 1991 Rothschild lecture:

Though most of my career has been devoted to the history of science, I began as a theoretical physicist with a strong avocational interest in philosophy and almost none in history. Philosophical goals prompted my move to history; it’s to philosophy that I’ve gone back in the last ten or fifteen years. (Kuhn, 1991/2000, p.106)

History of Science

Charles Gillispie (1918–2015), a major figure in the history of science community, reviewed Structure in 1962 and wrote: ‘Thomas Kuhn is not writing history of science proper. His essay is an argument about the nature of science’ (Gillispie, 1962, p.1251). But disarmingly, in as much as articulating the nature of science is a philosophical endeavour, Kuhn keeps saying he had no training in philosophy. Outside physics, Kuhn’s education fell between disciplinary stools.

Thomas Nickles, a philosopher sympathetic to Kuhn’s programme of historically informed philosophy, wrote:

Kuhn was always something of an amateur, largely self-taught in philosophy and even in history of science. (Nickles, 2003, p.9)

Kuhn may not have taken a PhD in history of science, but he did take his own teaching of history seriously. Stephen Brush, who took a Harvard General Education course of Kuhn’s, recalls:

In Kuhn’s seminar we learned that the history of science must be studied by careful reading of original sources. That means reading them in the original language, not relying on translations; it also means becoming aware of the precise meaning of technical terms by reading other works by the same author and works by other authors on the same subject at that time. One must be careful not to read modern meanings into older writings. (Brush, 2000, p.40)

This is the pedagogy of normal science in a history classroom. There was a lot to learn and be mastered before inquiry and negotiation began. And, as with science, doing the latter without the former was whistling in the dark.

Kuhn’s, 1978 Black-Body Theory and Quantum Discontinuity (Kuhn, 1978) is regarded by all commentators as his most substantial, archive-informed, and focussed historical work. The book, among other things, traces in detail Planck’s initial resistance to the new discontinuity theory of atomic radiation and the quantum effects, advanced by Einstein and others. It documents the tenacity with which Planck held on to the classical, continuous view of radiating energy. Trevor Pinch (1952–2021) a prominent ‘new wave’ sociologist of science, praised Kuhn’s ‘penetrating analysis’ of the relationship between Boltzmann’s statistical mechanics and quantum theory but, tellingly, points out that the book makes no mention of Structure. Further, none of the historiographic ‘apparatuses’ of Structure are utilised. Pinch remarked: ‘Kuhn has disregarded almost all the issues that grip current sociology and philosophy of science’ (Pinch, 1979, p.440) and has provided a ‘largely internal history of how discontinuity emerged at the turn of the century’ (Pinch, 1979, p.437). Pinch suggests that ‘it is quite possible’ that Kuhn’s indifference to his own ambiguous formulations meant that he was ‘unaware’ of the radical implications of Structure, and so could not carry them through in his serious historical study.

This is a problem for educators and others: The conceptual apparatus of the supposed blinding new Kuhnian light on our understanding of science is not even used by its author in his ‘display’ work. Further, Abner Shimony, the philosopher-physicist, in reviewing Kuhn’s book, wrote:

On the whole, the intellectual processes of the few physicists immersed in blackbody research seems to me to have been wonderfully rational. (Shimony, 1979, p.436)

Sociology of Science

Nickles, above, does not mention sociology which was at the core of Structure’s argument about the conduct of science and of scientific revolutions. From the beginning, Kuhn was sensitive to sociological factors in science. In 1952, he wrote to Philipp Frank:

It would seem to me that for any sociologist of science, it would be more fruitful to example the ubiquitous role of the sociology of the professional group than to concentrate solely on those factors (like government, church, etc.) which at this time and place have relatively little impact upon decisions made by professional scientists about problems arising within their own sciences. (Reisch, 2017, p.242)

This sensitivity meant he was attentive to the formative, educational influences, including textbooks, on the professional group and how that group’s dynamics bore upon research decisions. But this was sensitivity, not research. Arrestingly, Kuhn admitted that, when writing Structure, he ‘knew very little about sociology’ and further ‘he proceeded to make up the sociology of [scientific] communities as he went along’.47 In 1983, when receiving the John D. Bernal Award, he wrote:

Structure is sociological in that it emphasizes the existence of scientific communities, insists that they be viewed as the producers of a special product, scientific knowledge, and suggests that the nature of that product can be understood in terms of what is special in the training and values of those groups. (Kuhn, 1983, p.28)

But Kuhn continued:

Having insisted upon those points, however, I proceeded to make up the sociology of such communities as I went along, or rather to draw it from my experience with the interpretation of scientific texts supplemented by my experience as a student of physics. (ibid)

And admits:

That is an abominable way to do sociology, and it did not occur to me that its outcome would, qua sociology, have a claim on the attention of members of that profession. (ibid)

Kuhn made little, if any, effort to master extant literature in sociology of science. The argument of Structure seems not to have benefited from engagement with either J.D. Bernal’s work (Bernal, 1939) or that of Robert Merton, the founder of sociology of science (Merton, 1938/1973, 1942/1973). These fundamental works had been published 20 years before Structure. Merton’s, 1942 claim about the universality of scientific knowledge is assuredly something that Kuhn might have, for the benefit of everyone, profitably engaged with:

The cultural context in any given nation or society may predispose scientists to focus on certain problems … But this is basically different from the second issue: the criteria of validity of claims to scientific knowledge are not matters of national taste and culture. Sooner or later, competing claims to validity are settled by universalistic criteria. (Merton, 1942/1973, p.271)

Kuhn neither conducted nor oversaw empirical research studies on laboratory practice or any other scientific practice. His repeated admissions of ‘little training’ are striking and exemplify the argument of this paper: Kuhn consistently made claims about matters of which he, confessedly, knew little. Kuhn simply did no empirical sociology of science; he did not examine laboratories, research funding, political constraints or support, or control of journals. Barry Barnes, a founder of the powerful Edinburgh school of sociology of science, pointed to Kuhn’s superficial grasp of the practice of science:

In general, Kuhn’s work reveals little sensitivity to the highly differentiated structure of science and the importance of competition and mobility between different ‘schools’ or specialities. It leaves us unprepared for the finding that a combination of the skills of several specialties led to the elucidation of the structure of DNA and hence the creation of a new basic model for biological investigators. (Barnes, 1974, p.95)

A psychologist and a biologist, in a co-authored paper, drew attention to Kuhn’s distance from ‘coal face’ science and his subsequent misconceptions and underestimations of normal science:

Although Kuhn was trained as a physicist, he writes in the most general and vague terms about the scientific process and conveys little familiarity with the nuts and bolts of conducting research. Consequently, much of Kuhn’s analysis amounts to abstract speculation that bears little relation to how scientists normally think and what scientists normally do. (Sanbonmatsu & Sanbonmatsu, 2017, pp.134-135)

Some have thought that Kuhn’s account of normal science missed so much of its creativity, value commitments, and personal judgement that he was writing about something better described as ‘sub-normal’ science (Mody, 2015, p.99).

Science Classrooms

If Kuhn spent little time researching laboratory practice, he spent even less time researching science classrooms where, supposedly, the paradigms of science were being incubated and reproduced. Kuhn had been a student in physics classrooms and had taught in General Education classrooms, and so had inklings and intuitions about the impact of such instruction, but no education ‘research data’. Few sociology journals would publish any claim about purported scientific practice if there was no supporting empirical evidence. Yet founders of the Edinburgh Strong Programme in sociology of science consistently, as shown below, cite ‘evidence-free’ Kuhn as their inspiration, indeed their authority on the subject. Just the unpaginated citation ‘Kuhn’ was deemed sufficient to establish many contentious points.

The Limits of Overreach

That Kuhn had no immediate empirical evidence for his claims about the conduct of normal science, or for the processes whereby revolutions in science were initiated and accepted, does not mean that his claims are without warrant. Speculation in advance of evidence is standard scientific practice, but whether the speculation is correct, or justified, is something for the disciplines of philosophy, history, sociology, and perhaps social psychology to ascertain. Some did so and supported Kuhn; others did the same and rejected the Kuhnian picture. Thus the ‘Science Wars’ were constituted.48 It is a peculiar situation that so many professionals in these disciplines, including education, so lightly took Kuhn’s word for the book’s many philosophical, historical, and sociological claims. They adopted and promulgated the Kuhnian picture even when their interpretations were being rejected by Kuhn himself.

John Ziman (1925–2005), a physicist and educator, was sympathetic to Kuhn’s cross-disciplinary excursions. He saw this as a strength of Kuhn:

The deep message of THE STRUCTURE OF SCIENTIFIC REVOLUTIONS was that these jurisdictional disputes were futile. A scientific theory can only be grasped metascientifically as an entity with intertwined philosophical, historical, and sociological characteristics. … That is why we are all Kuhnians nowadays. (Ziman, 1983, p.24)

Doing research across the disciplinary board is as commendable as it is rare, but it does not mean that standards need not be reached; it just means that more of them need to be reached.

Wes Sharrock and Rupert Read, in their careful and sympathetic study of Kuhn, are decisive: ‘To say it again, Kuhn is a philosopher above all’ (Sharrock & Read, 2002, p.110). And it is as such that he needs ultimately to be understood and appraised. For them:

Kuhn, we have argued, neither provides a general and true theory of science, nor a set of normative prescriptions for how to pursue science correctly. (Sharrock & Read, 2002, p.210)

These two caveats take a large ‘bite’ out of Kuhnianism as a guiding educational, or any other, light. And should cause pause when reading David Treagust’s claim about Structure that opened this essay: ‘This small book really changed the way we look at the enterprise that is science’ (Treagust, 2022, p.16). What are the consequences of something so described by Sharrock and Read having such impact? What does it say about the science education community and its influence on public understanding of science?

Steven Weinberg (1933–2021), a physicist, historian, and Nobel laureate, observed that:

But even when we put aside the excesses of Kuhn's admirers, the radical part of Kuhn’s theory of scientific revolutions is radical enough. And I think it is quite wrong. (Weinberg, 1998)

Elaborating, he writes:

It is important to keep straight what does and what does not change in scientific revolutions, a distinction that is not made in Structure.There is a “hard” part of modern physical theories … that usually consists of the equations themselves, together with some understandings about what the symbols mean operationally and about the sorts of phenomena to which they apply. Then there is a “soft” part; it is the vision of reality that we use to explain to ourselves why the equations work. The soft part does change; we no longer believe in Maxwell’s ether, and we know that there is more to nature than Newton's particles and forces. (Weinberg, 1998)

There are important lessons to be learned about the academy, and culture more generally, from how Kuhn, untrained in any meta-scientific discipline, could have such an international impact and influence. Outside of science, this phenomenon is, depressingly, common. It is the mainstay of political and religious movements and associated rallies.49 Building HPS into teacher training programmes could mitigate it.

Kuhn’s Philosophy I: Undergraduate Encounter with Kant

As a Harvard undergraduate, Kuhn completed an elective ‘History of Philosophy’ course. He admits that not much of the course made an impression, but ‘Kant was a revelation’ (Baltas et al., 1997/2000, p.264).50

I gave a presentation on Kant and the notion of preconditions for knowledge. Things that had to be the case because you wouldn’t be able to know things otherwise.

Fifty years later, reflecting on that undergraduate episode and summarising his philosophy, he said:

Oh, it’s an important story because I go round explaining my position saying I am a Kantian with moveable categories. (Baltas et al., 1997/2000, p.264)

In his 1993 ‘Afterwords’ reflections on his career, Kuhn writes:

Though it is a more articulated source of constitutive categories, my structured lexicon [Kuhn’s new term for paradigm] resembles Kant’s a priori when the latter is taken in its second, relativized sense. Both are constitutive of possible experience of the world, but neither dictates what that experience must be. (Kuhn, 1993, p.331)

Due to the war, his Harvard programme was cut by a year, and so also cut was the possibility of him doing more philosophy courses. More is the pity as his Kantianism might have been refined or abandoned.51

Observation and Perception

Three years after graduating from Harvard with a physics PhD, Kuhn, in 1951, confidently strode into the philosophers’ domain when he wrote:

For scientific observation is always a process of abstraction. One abstracts the length, the color, the texture from a natural object which always provides an infinity of alternate abstractions. Some choice is demanded, and the choice must ultimately rest upon personal prejudice. (Kuhn, 1951/2021, p.17)

Understanding the epistemic function of observation and perception has been central to philosophy since at least Plato who affirmed that ‘we see through the eyeball, not with the eyeball’. Bacon and the British empiricists cemented the centrality of perception for science; Kant built a whole system by underwriting, and fleshing out, the observational foundations of Newtonian theory. The crucial role of observation for science was embraced by Mach and then by logical empiricism. On perception, Kuhn states the truism:

What a man sees depends both upon what he looks at and also upon what his previous visual-conceptual experience has taught him to see. (Kuhn, 1970a, p.113)

And he refers to research on the psychology of perception. Philosophers have also, since Plato, been writing on sensation, perception, and observation, but he largely ignored this tradition.52

Ontological Idealism and Epistemological Relativism

To the end, Kuhn held on to three foundational claims of Kantianism:

(i) Reality as it is (the noumena) is beyond our knowledge.

(ii) The known world, the world of which we can have knowledge (the phenomena), is constructed by us, and depends upon our cognitive machinery.

For Kant, the mind’s cognitive machinery—forms of sensibility and a priori categories, including, space, time, and causality—that it imposes on the noumena, is universal; they are part of having a human mind. Crucially, social constructivists, and cultural theorists in education, remove universality from the second bedrock and substitute cultural plurality. So, they post:

(iii) The concepts used to construct the known world vary among linguist, scientific and social groups. Consequently, they live in different worlds.

This third claim is not the banal truth that different people have different experiences in the same situation. This is so banal as to hardly warrant being called a claim. Consider, for example, a Chinese and an Australian standing in front of a sign:

The Chinese person has propositional perception STOP and behaves accordingly; the Australian simply has, at best, propositional perception SIGN and does not know what to do. The third claim above is the ontological claim that the real world, not the experiential worlds are different for different groups; they live in different real, not experiential, worlds. This is relativistic metaphysical constructivism, the philosophical position that became a best seller in the academy, and beyond.

A popular, and extended, statement of this third, socialised-ontology, position was Peter Berger and Thomas Luckmann’s The Social Construction of Reality. There they are adamant that ‘reality’ and ‘knowledge’ must be in scare quotes because these supposed realities always ‘pertain to specific social contexts’ (Berger & Luckmann, 1966, p.15). Their failure to distinguish reference from description, and their ontological conjuring, is endemic. At science education conferences, presenters use fingers to indicate that their use of ‘knowledge’, ‘truth’, ‘reality’, ‘proven’, and the like is not literal; finger movement shows that the presenter is not simple-minded and is not among the philosophically unwashed.

Observation, more correctly propositional perception, is theory dependent, but it is also nature dependent. Making basic observations has a strong survival value for animals. Science requires, in the way that non-sentient beings do not, that such observations be articulated as propositions—‘I see that p’ where p is some propositional statement.53 For example, ‘I see that there is a magnetic field’, ‘I see that President Biden is on TV’, and ‘I see that the proportion of tall plants is 1:3’. The practice of science requires the communication, and evaluation, of such observations. Propositional perception requires language, hence some level of theory, but there also needs be some state of affairs to be described. Not all communication need be propositional—gestures, pointing, expressions, body language, a whistle, or music can suffice in many circumstances—but not for scientific communication.

Kuhn’s Philosophy II: Separation of Truth from Science

In the 1970 Postscript, Kuhn famously, and for some infamously, said that truth was irrelevant to judgements of scientific progress:

Does it really help to imagine that there is some one full, objective, true account of nature and that the proper measure of scientific achievement is the extent to which it brings us closer to that ultimate goal?’ (Kuhn, 1970a, p.171)

Separating truth from science was a major break from orthodox understanding. Kuhn repeats his pre-Structure conviction:

We can have no recourse to notions like the ‘truth’ or ‘validity’ of paradigms in our attempt to understand the special efficacy of the research which their reception permits. (Kuhn, 1963, p.358)

This is subsequently elaborated as:

There is, I think, no theory-independent way to reconstruct phrases like ‘really there’; the notion of a match between the ontology of a theory and its ‘real’ counterpart in nature now seems to me illusive in principle. (Kuhn, 1970a, p.206)

The separation is maintained twenty years later, in his ‘Afterwords’ contribution to a 1990 MIT conference dedicated to appraising the gamut of his philosophical and historical claims. There he makes a much-referenced claim with ontological and epistemological dimensions:

On the one hand, I aim to justify claims that science is cognitive, that its product is knowledge of nature, and that the criteria I use in evaluating beliefs are in that sense epistemic. But on the other, I aim to deny all meaning to claims that successive scientific beliefs become more and more probable or better and better approximations to the truth and simultaneously to suggest that the subject of truth claims cannot be a relation between beliefs and a putatively mind-independent or ‘external’ world. (Kuhn, 1993, p.330)

Concerning ontology, his use of scare quotes around ‘external’, and reference to ‘putative’ reality, suggests, if not downright means, that, for Kuhn, there is no such thing as an external, observer-independent world. Otherwise, why use such quotes?

He elaborates puzzle solving, not truth-finding, as the goal of science. Twenty years after publication, and despite all the criticism, he writes that his claim in Structure was the ‘right one’ (Kuhn, 1993, p.338). But Kuhn says his reader has to:

… set aside the notion of a fully external world toward which science moves closer and closer, a world independent, that is, of the practices of the scientific specialties that explore it. (Kuhn, 1993, p.338)

Again, what function and purpose does ‘fully’ play in this claim? Might an external world be partly dependent upon the observer? Seemingly, for Kuhn, this is so. This, at best semi-idealism, was clearly stated in the first edition, and it was not retracted in the second, nor thereafter:

I have so far argued only that paradigms are constitutive of science. Now I wish to display a sense in which they are constitutive of nature as well. (Kuhn, 1970a, p.110)

This is the beginning of an ontological idealist slope that ends, as John Passmore observes, in ‘the French intellectual’s dream … of a world that exists only in so far as it enters into a book’ (Passmore, 1985, p.32). There are many social constructivists, in and out of education, lining the slope, and cheering all who slide down it.

Concerning epistemology, if truth is taken off the science table, then what is progress toward? Economic betterment? Political power? Research funds? All Kuhn offered was better ‘puzzle solving’. In the Postscript, he writes:

Taken as a group or in groups, practitioners of the developed sciences are, I have argued, fundamentally puzzle-solvers. (Kuhn, 1970a, p.205)

And once they are initiated into their puzzle-solving craft:

Whether or not individual practitioners are aware of it, they are trained to and rewarded for solving intricate puzzles be they instrumental, theoretical, logical, or mathematical at the interface between their phenomenal world and their community’s beliefs about it. (Kuhn, 1993, p.338)

As with so much of Kuhn, readers need to pass quickly over clauses such as ‘the interface between their phenomenal world and their community’s beliefs about it’. Staying too long and asking: ‘What does this mean?’ makes for very slow reading without guarantee of any resolution.

Shape of the Earth

Demonstrably, competing theories can be appraised with respect to how adequately or approximately they depict the world. Consider the 2000 + years investigation of the Earth’s shape. Pythagoras’ 500bc claim that the Earth is spherical is closer to the shape of the Earth, and was progressively seen to be so, than competing claims that the Earth was flat. Until the fifteenth century, official Chinese astronomers (and there were no astronomers apart from official ones) were ‘flat earthers’. This is seen in the important early fourteenth-century astronomy book, Ge xiang xin shu, written between 1324 and 1335 by the Daoist priest and astronomer Zhao Youqin. In his version of neo-Confucian cosmology, the earth is likened to a flat board floating on water, with China in its centre, and surrounded by the heavens; the cosmos had a globular or egg structure.

In 1583, Matteo Ricci the Jesuit priest, astronomer, and natural philosopher began his mission to China (Brockey, 2008). He advanced the Copernican system, though it was banned in Rome, against official ‘flat earthers’. His accurate predictions of the 1601 solar eclipse in comparison to the failure of the court astronomers made such an impact on the Ming Emperor Wanli that the Copernican spherical earth theory became official policy.54 Scientific understanding could be, and was, shaped by how the world was.

In the eighteenth century, the spherical theory was adjusted. The realisation that the seconds pendulum was slowing at the equator prompted refined views about the Earth’s supposed spherical shape. Some, the ‘squeezers’, constricted the equator; others, the ‘flatteners’, expanded it. The latter, who included Newton, eventually won a debate that folded metaphysics, theology, mathematics, national interest, and technology into science.55 Thereafter, belief in the spheroidal, oblate Earth became the cultural and scientific norm. Different of Darwin’s theories of evolution might not fully ‘capture’ the natural realities of evolution, but they do better than Special Creation and so on across the landscape of science. Why agree with Kuhn’s denial of any meaning to ‘claims that successive scientific beliefs become more and more probable or better and better approximations to the truth’? Progressively, the true shape of the Earth was ascertained. Contra Kuhn, John Worrall sensibly writes:

It seems difficult to deny, I suggest, that the development of science has been, at least to a very good approximation, cumulative at the observational or experimental level. (Worrall, 2002, p.32)

Pseudoscience

It is of significant philosophical and social importance to distinguish science from pseudoscience. With difficulty, this can be done.56 But if science in its totality is just puzzle solving, as Kuhn would have it, without a voice from the world, then the separation of scientific puzzle solving from pseudo puzzle solving becomes impossible. Any book of pseudoscience is full of solved puzzles; most pseudoscience websites will, for a fee, solve your puzzle. Most pseudosciences have a large or small dash of technology which might well solve puzzles. But technology is not science. In addition, there are personal and social consequences of not distinguishing science from pseudoscience. Why set up ‘Truth and Reconciliation’ commissions if there is no truth to be found?57

Kuhn’s Philosophy III: Anti-Realism

The realism/anti-realism divide is perhaps the longest-running debate in philosophical reflection on science beginning at least when Aristotle asserted his realism against forms of Platonic idealism. The modern form of the debate was initiated when the Protestant scholar Andreas Osiander inserted an unsigned Preface into Copernicus’s 1543 On the Revolution of the Heavenly Spheres. The instrumentalist preface asserted that Copernicus’s Earth was not really revolving, and it was just said to be so in order to simplify astronomical calculations. Galileo famously upheld the realist reading of Copernicus. Only under inquisitorial pressure did he formally adopt an anti-realist, instrumentalist position.58 Publication of Structure brought this philosophical debate to quarters hitherto unaware of it.

Ernan McMullin (1924–2011) correctly recognised that ‘The radical challenge of Structure is directed not at rationality but at realism’ and went on to observe that ‘Kuhn’s influence on the burgeoning anti-realism of the last two decades can scarcely be overestimated’ (McMullin, 1993, p.71). Kuhn concurred with McMullin’s, and earlier critics’, charges of anti-realism:

Despite my critics, I do not think that the position developed here leads to relativism, but the threats to realism are real and require much discussion, which I expect to provide in another place. (Kuhn, 1990, p.317)

The threats do require more discussion than Kuhn gave them. Some have endeavoured to elaborate, and make consistent, Kuhnian anti-realism. One such interpreter, Michela Massimi, does add the obvious proviso that ‘Kuhn’s view is either relativist or realist; it cannot be both at the same time’ (Massimi, 2015, p.143).

There are a variety of realisms.59 One book, titled Varieties of Realism, has 22 contributions (Agazzi, 2017). In recent decades, three dominant variants have emerged: Structural Realism advanced by John Worrall (Worrall, 1989), Ontic Structural Realism advanced by both Steven French (French, 2017) and James Ladyman (1998), and Selective Realism advanced by Alberto Cordero (Cordero, 2017).

Realism maintains that there exists an observer-independent world, that scientific theories make claims about both observational (compass needle movements) and non-observational (magnetic fields) things in that world, that those claims are approximately true, and that scientific progress occurs and is marked by widening and deepening the pool of such true and approximately true claims. Realist positions share the following commitments:

An ontological commitment to the reality and independence of the world: external things and events, including unobservable and inferred entities, exist independently of cognising subjects.

A semantic commitment to the linkage of scientific claims to external things and events: science makes claims about the world.

An epistemological commitment: namely, that science has made some truthful, or approximately truthful, claims about entities