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Thomas Kuhn Wasn't So Bad

A former student of the influential philosopher defends him against filmmaker Errol Morris’s “character assassination” 

James McClellan, who studied under Thomas Kuhn (above) in the early 1970s, says he was a realist and a relativist, a bully and a kind man. Truth is complicated, like Kuhn said.

Bill Pierce Getty Images

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


In a recent post I review The Ashtray (Or the Man Who Denied Reality), filmmaker Errol Morris’s takedown of philosopher-historian Thomas Kuhn. Morris claims that Kuhn was a bad person and bad philosopher, who threw an ashtray at him in 1972, when he was a graduate student. My friend and colleague James McClellan, a distinguished historian of science at Stevens Institute of Technology, was also Kuhn’s student in Princeton the early 1970s. Eager to get Jim’s take on Ashtray, I gave him a copy, and he rewarded me with this response. –John Horgan

Dear John,

Thank you so much for your gift of Errol Morris’ The Ashtray.


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For reasons I’ll explain, I had trouble fighting my way through this book, but reading it was a social and intellectual nostalgia trip of the highest order for me. I was a graduate student myself in the Princeton history of science program at the time of “the incident.” My wife Jackie and I knew and loved Errol, an ebullient genius himself, as his future career amply demonstrates. (I vividly remember his triumphant return to a party going on at our house after his famous escape from jail in Trenton as an anti-war protester!) We were good friends with Norton Wise, for example, who figures in Errol’s narrative, too.

Mostly in this context, I knew Tom Kuhn and had regular dealings with him over my five years in the Princeton program from 1970 to 1975. Kuhn taught the seminar for entering graduate students the year I arrived. (Can you imagine? Although what we were supposed to gain from a close reading of Anneliese Maier is still a mystery to me.) The following year Kuhn recruited me into his seminar on the prehistory of thermodynamics, and knowing that my mathematical skills couldn’t handle, say, Clausius, he assigned me the introductory sessions on Lavoisier and the caloric theory of heat and Count Rumford on heat as a mode of motion. (Out of this seminar came his landmark piece on simultaneous discovery.) The year after that Kuhn was an examiner on one of my qualifying exams, this one on the Scientific Revolution. (I passed, if barely.)

More than that Kuhn was a fixture in Princeton and in the Princeton program whom everyone knew well and, I daresay, at least respected. We all socialized at the weekly Program sherry parties that took place after his seminar, complements of the Ford Foundation. (Ah! The Ivys!) He was a regular in the study room reserved for the historians of science in the basement of Firestone Library. Jackie and I spotted him once in tennis attire driving down Nassau Street in a convertible trailing cigarette smoke behind, and again at a basketball game where he tried gamely to keep score in a scorebook given to him by his children. He once slummed at a party at our decrepit graduate student digs, where joints circulated freely.

Errol’s book is a masterpiece of rhetoric and character assassination: do we really need the illustration of Louis XVI’s bloody head raised at the guillotine? Yes, Kuhn could be a bully, especially towards anyone who challenged him, such as Errol or our late colleague Harold Dorn. But for someone like myself, non-threatening and interested in science and the Enlightenment, Kuhn was kind and took his responsibilities seriously as a teacher. The first draft of my paper for his thermodynamics seminar was a disaster, but he took the time and trouble (and only 1-1/2 pages of single-spaced typed response) toward guiding me to see its flaws, and he taught me the simple, but invaluable lesson that before you write, you have to know what you want to say.

We ordinary mortals – and I certainly did – thought that Kuhn was a superior genius, someone with super-human brain power, as if his cerebral cortex had another layer the rest of us lacked. He seemed to suffer in thinking, and always with a smoke and three steps ahead of any interlocutor, he could abide not three sentences before his characteristic interjection, “Look,…,” followed by complex corrections and qualifications. His writing reflects his tortured thought as well. Leaving aside his angst and guilt, Kuhn reminds me of Galileo, Galileo’s incomparable intellect, and Galileo’s well-merited intolerance.

What is left out of Errol’s account and today’s considerations of Kuhn are the historiographical circumstances of the 1950s and 1960s that gave rise to Kuhn’s work in the first place. Post-modernism and the social construction of knowledge came later. We forget the triumphant historiography and bedazzled public view of science that emerged after WWII. Recall that Charles Gillispie, my mentor and the man responsible for bringing Kuhn to Princeton, in 1959 published The Edge of Objectivity, an account purportedly documenting those transitions where inchoate knowledge of nature metamorphosed into true science.

Back then science was seen as having a distinct method and as the triumphant and seamless layering of one secure brick of knowledge on top of another. Whatever else we may think of Kuhn’s Structure of 1962, he killed Whiggism. He showed once and for all that the history of science has been marked by fundamental discontinuities (revolutions), and he was supremely creative in outlining processes involved in scientific change. These are major and incontrovertible contributions to our understanding of science and its history. 

Beyond that, the historiography of science in the 60s and 70s centered on distinctions between the “internal” history of science, or the internal logic of scientific ideas and their disembodied development over time, and the “external” history of science, or the grubby social and institutional contexts in which serene natural philosophers built on the work of their predecessors. What fucked Kuhn up is that he was always an internalist, and when social construction and post-modernism came down the pike he had to reconcile his views of the internal development of scientific ideas (and their methodological and epistemological consequences) with this cascade of new and troubling sociological perspectives. I remember asking Kuhn in the 70s about how we should bridge the gap between the internal and the external, and he tepidly suggested focusing on different generations of scientific practitioners, but he didn’t seem to care, really. (Even into the 1980s Arnold Thackray at the Department of History and Sociology of Science at Penn was arguing for prosopography, or collective biography, as the way forward to bridge the internal-external debate.)

Of course, all that came crashing down, Errol and Steven Weinberg notwithstanding, when it became clear that science is fundamentally a social activity and scientific claims are socially constructed by practitioners, admittedly trying their best to say something solid about the natural world around us. Kuhn’s views of 1962 had to be fitted in to and defended in this radically new intellectual context. He did his best despite the disdain of establishment philosophers, who never accepted him as a legitimate voice. 

I am not a philosopher myself, and thus also have no standing in this discussion, but the answers to Errol’s dilemma have long seemed clear to me: that is, Kuhn is a realist, in that he believes in some external, material reality beyond our language and cultural constraints, but he is simultaneously a relativist in that he has no access to nor can say anything definitive about that outside world independent of language and the conceptual categories that lead us to think this or that about external reality. Moreover, against more radical relativist positions, which he eschewed, Kuhn holds that some stories are better than other stories. For that reason, then, Errol’s attack on Kuhn as leading to Trump, “fake news,” and an unmitigated intellectual or political free for all where anything goes falls short. 

No one wants to go back to Aristotelian or Newtonian physics for good reason, but we need to also acknowledge that our current thought categories are dynamic, not fixed. And here, Kripke’s notion of reference fails, at least in my estimation, not only considering that the thing referenced cannot be understood or grasped independently of language and society, but also because the very concepts – the moon, an electron – themselves are constantly in flux and change with every slight iteration, all of which leaves the target reference even more inaccessible and vacuous. If Errol or Kripke or anyone can tell me something absolutely objective and unchanging about what’s out there in the natural world, I sincerely want to hear and believe that. Maybe I should (re)turn to Jesus.

Your friend, Jim

Further Reading:

Jim McClellan makes an appearance in my new online book Mind-Body Problems (see introduction) as well as previous blog posts (Cantankerous Historian of Science Questions Whether Science Can Achieve “Truth” and Science, History and Truth at the Faculty Club).

I discuss Morris’s views of Kuhn in three previous columns: Did Thomas Kuhn Help Elect Donald Trump?, Second Thoughts: Did Thomas Kuhn Help Elect Donald Trump? and Filmmaker Errol Morris Clarifies Stance on Kuhn and Trump.

What Thomas Kuhn Really Thought about Scientific "Truth"

Was Philosopher Paul Feyerabend Really Science's "Worst Enemy"?

The Paradox of Karl Popper

Mind-Body Problems (free online book)

For other takes on Ashtray, see reviews by Tim MaudlinDavid Kordahl and Philip Kitcher and a blog post by Kuhn’s son Nat.