Thomas Kuhn

"Kuhn as does Popper rejects the idea that science grows by accumulation of eternal truths.. But while according to Popper science is ‘revolution in permanence’, and criticism the heart of the scientific enterprise, according to Kuhn revolution is exceptional and, indeed, extra-scientific, and criticism is, in ‘normal’ times, anathema... The clash between Popper and Kuhn is not about a mere technical point in epistemology. It concerns our central intellectual values, and has implications not only for theoretical physics but also for the underdeveloped social sciences and even for moral and political philosophy. If even in science there is no other way of judging a theory but by assessing the number, faith and vocal energy of its supporters, then this must be even more so in the social sciences: truth lies in power. Thus Kuhn’s position would vindicate, no doubt, unintentionally, the basic political credo of contemporary religious maniacs (‘student revolutionaries’)."

"What, then, is the hallmark of science? Do we have to capitulate and agree that a scientific revolution is just an irrational change in commitment, that it is a religious conversion? Tom Kuhn, a distinguished American philosopher of science, arrived at this conclusion after discovering the naivety of Popper’s falsificationism. But if Kuhn is right, then there is no explicit demarcation between science and pseudoscience, no distinction between scientific progress and intellectual decay, there is no objective standard of honesty."

"What truth is not, according to Kuhn, is an accurate representation of the world as it is in itself. Scientific theories represent a world, but one partially constituted by the cognitive activities of the scientists themselves. This is not a commonsensical view, but it has a distinguished philosophical pedigree, associated most strongly with Kant. The Kantian view is that the truths we can know are truths about a ‘phenomenal’ world that is the joint product of the ‘things in themselves’ and the organising, conceptual activity of the human mind. Kuhn, however, is Kant on wheels. Where Kant held that the human contribution to the phenomenal world is invariant, Kuhn’s view is that it changes fundamentally across a scientific revolution. This is what he means by his notorious statement that, after a scientific revolution, ‘the world changes’. This is neither the trivial claim that scientists’ beliefs about the world change, nor the crazy claim that scientists can change the things in themselves simply by changing their beliefs. It is the claim that the phenomenal world changes because the human contribution to it changes."

"The Structure of Scientific Revolutions contains some nice observations on the nature of what Kuhn calls “normal science”, which makes it out to have none of the heroic aspects that Popper insisted on. But when Kuhn goes beyond normal science to “revolutionary science” the book is a disaster. It promotes an irrationalist view of scientific revolutions that is both false and pernicious. The Copernican Revolution is a lovely book, much needed at the time. Planck and the Black Body Discontinuity is a mixed bag: some good historiography and some poor analysis."

"Kuhn's description of how scientific revolutions happen does not apply to any biological revolution. To be very frank, I cannot understand how this book could have been such a success. The general thesis was not new, and when he did assert specific claims he was almost always wrong! Kuhn's book mainly appealed to historians and social scientists. It was they who built it up into a big thing. It was vague, and vagueness always appeals to historians and social scientists."

"Much of what Kuhn says about great theoretical shifts, and the inertial role of long-established scientific paradigms and their cultural entrenchment in resisting recalcitrant evidence until it becomes overwhelming, is entirely reasonable, but it is also entirely compatible with the conception of science as seeking, and sometimes finding, objective truth about the world. What has made him a relativist hero is the addition of provocative remarks to the effect that Newton and Einstein, or Ptolemy and Galileo, live in "different worlds," that the paradigms of different scientific periods are "incommensurable," and that it is a mistake to think of the progress of science over time as bringing us closer to the truth about how the world really is."

"This brutal summary of the revolutionary process does not do justice to the complexity and subtlety of Kuhn's thinking. To appreciate these, you have to read his book. But it does perhaps indicate why Structure… came as such a bombshell to the philosophers and historians who had pieced together the Whig interpretation of scientific progress."

"When Thomas Kuhn talked about paradigm shifts within science, he defined a paradigm as a disciplinary matrix, which included not just the dominant theoretical framework within a given science (say, quantum mechanics in modern fundamental physics), but also the vocabulary and methods accepted within the community, the range of questions deemed interesting, as well as the textbooks and other training tools for the next generation of scientists. In a very real sense, then, physics, biology, analytical philosophy, continental philosophy, and so forth are indeed “traditions,” and the best (if not the only) way to learn them is not just by reading books at home, but by engaging in personal training over a number of years. That’s one reason why lone individuals who style themselves as revolutionary geniuses and who are convinced to have discovered proof that, for instance, general relativity is flawed are (much) more likely to be cranks than anything else. And that is also why, again in part, pseudoscience has a very different character from the genuine article."

"Kuhn’s (and Feyerabend’s) account of the historical development of science threatens inductivist and hypothetico-deductivist methodologies in a straightforward and dramatic way. When we look at what past scientists do, their work does not seem to fit the methods described by either inductivists or hypothetico-deductivists. Scientists engaged in normal science are pursuing neither confirmations nor refutations of their theory. They are engaged in an activity that Kuhn calls articulating the paradigm, which as we have seen involves many things other than theory testing. That is an important negative conclusion, and the method of arriving at it should appeal to the naturalist. The argument is essentially an empirical one. The history of science refutes (or at least shows the inadequacy of) the most popular methodologies of science. But Kuhn’s and Feyerabend’s description of scientific revolutions also presents two problems for the naturalist. First, since both claim that there is never a compelling reason to change from one paradigm to another, their accounts of science threaten to make scientific change look irrational. If that story is right, it should shake the naturalists’ conviction that science is to be admired as much as they think. Secondly, even if we could retell the story of scientific progress to remove some of the arbitrariness that Kuhn and Feyerabend claim exists; even if we could explain why scientists have changed paradigms and thereby methods from one period to the next, then we shall still have to confront another issue. If the methods of science have changed through history, that means there is no such thing as the scientific method, and so obviously no way to make use of the methods of science in philosophy."

"Up until the publication of Thomas Kuhn's The Structure of Scientific Revolutions in 1962, the history, philosophy, and sociology of science maintained an internalist approach to scientific knowledge claims. Science was seen as somehow above any social, political, or cultural influences, and therefore, the examinations of scientific knowledge focused on areas such as 'discoveries,' 'famous men,' and 'the scientific revolution in the West.' When Kuhn opened the door to the possibility that external factors were involved in the development of scientific paradigms, science studies assumed a more critical tone."

"Whatever Kuhn’s intentions, I believe that his effect on general culture, though not on the practices of real scientists, has been unfortunate, because it has served to “demythologize” science, to “debunk” it, to prove that it is not what ordinary people have supposed it to be. Kuhn paved the way for the even more radical skeptical view of Paul Feyerabend, who argued that as far as giving us truths about the world, science is no better than witchcraft."

"Finally, by the early 1960s, Thomas Kuhn’s picture of “normal science” portrayed scientific activity not as an open-minded philosophical quest but as puzzle-solving—the extension and application of existing paradigms. To the shock and indignation of some, Kuhn argued that being a scientist involved obedience to “dogma” and a narrowing of perception. Science remained, of course, the most reliable knowledge we had, but whatever moral authority might follow from regarding science as uniquely free of prejudice was—for those persuaded by Kuhn—no longer available."

"To put the mater simply, I think that Kuhn might have vastly overemphasized the role of scientific revolutions. I also don’t believe that an evolutionary view can be compatible with Kuhnian discontinuities."

"Not long after publication of my first article on the subject, I was given a book called The Structure of Scientific Revolutions written by the philosopher of science Thomas Kuhn. This book deals with the process by which scientific paradigms are produced and replaced. I warmly endorse this book because I have lived through several of the stages described in the book."

"I’m one of the few physicists I know who likes Thomas Kuhn. He was partly a historian of science, partly a sociologist. He got the basic idea right of what happens when the scientific paradigm shifts. A radical change of perspective suddenly occurs. Wholly new ideas, concepts, abstractions and pictures become relevant. Relativity was a big paradigm shift. Quantum mechanics was a big paradigm shift. So we keep on inventing new realisms. They never completely replace the old ideas, but they do largely replace them with concepts that work better, that describe nature better, that are often very unfamiliar, that make people question what is meant by “reality.” Then the next thing comes along and turns that on its head. And we are always surprised that the old ways of thinking, the wiring that we have or the mathematical wiring that we may have created, simply fail us."

"Although Kuhn's emphasis on revolutionary change was an antidote to the simplistic models of the logical empiricists, a finer-grained theory of revolutionary change than Kuhn presented need not succumb to irrationalism. To develop such a theory, however, we need tools different from both the formal ones of the logical empiricists and the vague historical ones of Kuhn."

"[The Structure of Scientific Revolutions] was hugely influential, especially on the liberal arts, giving them ammunition to suggest that science was no better way of knowing the truth than any other way of investigating. It made a huge case of scientists gathering around one truth, and then there’s a tipping point and everyone moves away from that truth to gather around another truth. Hence the title of the book. And this left people with the sense that science is just whatever is in fashion. Kuhn used, as his best example of this, Copernicus. That’s half his book ... almost half of that book describes the Copernican Revolution as an example of the way science works. But that’s not how science works. It’s just not. It’s how things happened until 1600."

"In his celebrated book The Structure of Scientific Revolutions Thomas Kuhn went a step further and argued that in scientific revolutions the standards (or “paradigms”) by which scientists judge theories change, so that the new theories simply cannot be judged by the prerevolutionary standards. There is much in Kuhn’s book that fits my own experience in science. But in the last chapter Kuhn tentatively attacked the view that science makes progress toward objective truths: “We may, to be more precise, 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.” Kuhn’s book lately seems to have become read (or at least quoted) as a manifesto for a general attack on the presumed objectivity of science."

"The changes in the way we judge our theories have bothered philosophers and historians of science. Thomas Kuhn’s early book, The Structure of Scientific Revolutions, emphasized this process of change in our scientific standards. I think Kuhn went overboard in concluding that there was a complete incommensurability between present and past standards, but it is correct that there is a qualitative change in the kind of scientific theory we want to develop that has taken place at various times in the history of science. But Kuhn then proceeded to the fallacy—much clearer in what he has written recently—that in science we are not in fact moving toward objective truth. I call this a fallacy because it seems to me a simple non sequitur. I do not see why the fact that we are discovering not only the laws of nature in detail, but what kinds of laws are worth discovering, should mean that we are not making objective progress."

"By the way, in this respect my friend Thomas Kuhn has a lot to answer for. He distances himself from the postmoderns and the social constructivists, but he is endlessly quoted by them. He distances himself in saying that there is a place for evidence and reason in the scientific process—good to hear—but he attacks the idea that we are moving toward objective truth. As far as I can tell from one of his recent articles, his reason for rejecting the idea that science moves toward objective truth is that he and other philosophers have not succeeded in defining truth—and he cannot say what truth would be. This seems a bit like saying that because farmers cannot define cows or the difference between cows and, say, buffaloes, one should doubt the objective existence of cows. I would argue that it’s not the job of farmers to define cows; that’s the job of zoologists. Likewise, it’s not the job of physicists or other scientists to define truth; that’s the job of philosophers. If they haven’t done that job, too bad for them. But just as the farmer generally knows cows when he sees them, we scientists usually know truth when we see it."

"Now, that really was a paradigm shift. For Kuhn it seems to have been the paradigm of paradigm shifts, which set a pattern into which he tried to shoehorn every other scientific revolution. It really does fit Kuhn's description of paradigm shifts: it is extraordinarily difficult for a modern scientist to get into the frame of mind of Aristotelian physics, and Kuhn's statement that all previous views of reality have proved false, though not true of Newtonian mechanics or Maxwellian electrodynamics, certainly does apply to Aristotelian physics. Revolutions in science seem to fit Kuhn's description only to the extent that they mark a shift in understanding some aspect of nature from pre-science to modern science. The birth of Newtonian physics was a mega-paradigm shift, but nothing that has happened in our understanding of motion since then—not the transition from Newtonian to Einsteinian mechanics, or from classical to quantum physics—fits Kuhn's description of a paradigm shift."

"Kuhn rejected our old metaphysics—consciousness consists of an inner representation of an outer reality—as incoherent, impossible, and fundamentally inhuman. That's why he begins SSR by invoking history not as a discipline that can be applied to science, but as a necessary part of scientific understanding. … The problems that dominated Kuhn's life after his great moment of insight arose not because Kuhn wasn't brilliant enough. Rather, they arose and persist because while we increasingly understand that the old metaphysical paradigm has failed, for several generations now we have not found our new paradigm."

"The Road since Structure is a collection of essays by Kuhn along with a lengthy interview with him conducted in 1995 by Aristide Baltas, Kostas Gavroglu, and Vassiliki Kindi. The essays form part of Kuhn’s thirty-year effort to clarify the contrast between paradigm shifts and normal science, with a focus on philosophical issues. For example, Kuhn alarmed many scientists with his claim that, while science makes progress, this progress is not towards truth but rather involves never-ending change through paradigm shifts. But the scientists have not realized that Kuhn’s claim is based on a philosopher’s definition of “truth,” which is not achieved (if ever) until there is exact knowledge of the ultimate constituents of matter on the quantum-gravity scale. Scientists use a less demanding definition for the word “truth,” in which measured parameters can be subject to nonzero error bars."

"Thomas Kuhn believed that a science has to become a "paradigm", with a shared technical language that excludes outsiders, before it can get any real work done. In the formative stages of a science, according to Kuhn, the adherents go to great pains to make their work comprehensible to outside academics. But (according to Kuhn) a science can only make real progress as a technical discipline once it abandons the requirement of outside accessibility, and scientists working in the paradigm assume familiarity with large cores of technical material in their communications. This sounds cynical, relative to what is usually said about public understanding of science, but I can definitely see a core of truth here."