“A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die…”

8 May 2011

Thomas Kuhn quoting Max Planck.

Science is about Ideas – ideas that stick. Well, perhaps that should be the history of science is about ideas. Science as it is practiced is mostly about going in to work in the morning, reading, having lunch, writing, checking emails, going on facebook, having a drink after work, intermixed with a bit of pipetting, measuring and so on. You know, a normal job.

My namesake Thomas (Kuhn) in his famous book, The Structure of Scientific Revolutions argued that science does not proceed by scientists formulating a hypothesis, then testing it with experiment  – and if disproved, dispassionately  concluding their hypothesis to be false and moving on. Rather, Kuhn pointed out that if an experimental result doesn’t fit with the generally accepted scientific model, they will either reject the experiment as flawed or inaccurate, or, instead of regarding the hypothesis as disproved, they’ll extend or alter it slightly so as to incorporate the odd result. This Kuhn called Normal Science – which is how science operates most of the time. Researchers work inside the current paradigm, which allows them to get on with ‘puzzle solving’ – that is, focussing on the details without having to question the fundamentals of their discipline. In this way they reinforce the current paradigm rather than attempting to falsify it. If an individual researcher claims that they’ve found out the current paradigm is fundamentally flawed, or questions it’s underlying assumptions, then they’ll be outcast as a scientific heretic.

However, eventually, so much extending of the paradigm has been necessary, that a new paradigm arises to account for the overwhelming amount of results which don’t fit. The proponents of the new and old paradigms battle it out for a while, (basically until the old guard die off), and the new paradigm becomes the generally accepted model – a paradigm shift has taken place.

Can you say that the new paradigm is better than the old one, or that it’s ‘true’ and the superseded paradigm is false?

According to Jane Gregory (and other philosophers of science), the only way of deciding between one paradigm or another, is on the basis of which one gives us answers that are ‘most helpful’, or even the answers that we ‘want’. . .

3 Responses

  1. I loved your article.Really looking forward to read more. Keep writing.

  2. […] Paradigm Shifts back to top ↑ […]

  3. Josbert says:

    here is sensible and well taken. It has clartiney been influential, perhaps in ways the author never intended, and should be read for that reason. But there are odd omissions. The greatest paradigm shift in physics since Newton the adoption of fully-fledged quantum mechanics after 1925 finds no significant place in this study. Eminent physicists, including Einstein, and even Schrodinger, one of its founders, regarded the new paradigm with deep distaste on aesthetic and philosophical grounds. Yet the methodology was adopted universally almost at once. What sociological factors, what structures of power and patronage brought this about? We are not told.It is when Kuhn puts on his philosopher-of-science hat and tells us about the incommensurability of paradigms’ that we should question what he means, and more especially what some people have read into it. The idea is that Archimedes or Aristotle, encapsulated in their ancient world-view, would have been unable to see what Newton was getting at in his Principia’; and likewise Newton if you gave him a copy of Dirac’s Quantum Mechanics’. This has been held to have implications for epistemology, viz: it is a mistake to think of the evolution of science (or any rational endeavor) as progress’ in the sense of bringing us closer to an accurate picture of the world. Kuhn’s position can be likened to Darwinian evolution: progress *from*, yes; progress *towards*, no. There is room here for fancy footwork. But the finer points are lost on some who simply cheer it as a poke in the eye for rationality.If an epochal break can be found anywhere in the history of science, it is in the transition from the Aristotelian to the modern world-view which took place in early modern times. Since then nothing remotely like it has happened. The training of physicists still begins with a detailed study of Newtonian mechanics, which for many purposes, from shooting pool to spaceflight, provides an entirely adequate description. An important part of learning relativity or quantum mechanics lies in understanding how they fit in with Newtonian physics in fact, precisely how the paradigms are commensurable where their domains overlap. The same people at different times use the paradigm of Newton and the paradigms of Einstein and Bohr/Heisenberg. They don’t use the paradigm of Aristotle or the New Age paradigm because interesting though these are to the historian or the social scientist they don’t work; they are not fruitful for puzzle-solving, Kuhn would say.A process of generalization of paradigms has been characteristic of physics for the past few centuries, and this seems true of mature sciences generally. At the fundamental level a paradigm that has proven really useful is hardly ever scrapped (Kuhn cites two cases from physics since Newton: the recurring controversy over the nature of light both sides seem to have won that one and the caloric theory of heat). Instead, the old paradigm is subsumed into a more developed theory with a broader domain of application, yielding in some sense deeper insights. Kuhn the physicist knew this, of course, though some of his readers don’t; so he had to defend the unusual position that e.g. Newtonian mechanics is fundamentally incompatible with Einsteinian mechanics, even though one is a limiting case of the other (Kuhn disputed this) and both are used successfully all the time. This was the only way he could maintain that they are incommensurable’.Where does this leave the incommensurability of paradigms? The concept can be interpreted according to taste along a spectrum: at one end, true but trivial; at the other end, deep but almost clartiney false. Indeed and I’m going to be shockingly naive here you wouldn’t be reading this otherwise; you’d be chipping flints. For what it’s worth, my opinion is that Newton, far from living in a different world’, would be perfectly at home with modern physics and raring to go, given a couple of years to get up to speed; Archimedes might take a little longer, while Aristotle would be a leading light at the Sorbonne.More problematic even than incommensurability of paradigms in Kuhn’s work are occasional gnomic statements such as the following: 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 and Scientific knowledge, *like language*, is intrinsically the common property of a group *or else nothing at all* (my italics).Taken with the thesis of the book (though Kuhn denied it) remarks like these open the door to all the baggage of so-called radical relativism. Now the baggage is in the hall and halfway up the stairs, as Gross Levitt, Sokal Bricmont and others have pointed out. Some of us wish it was out back in the hen-house.At the heart of modern physics there is indeed an incommensurability, in at least one of Kuhn’s senses. It is between the two fundamental theories, general relativity and quantum mechanics. That doesn’t stop people from using both paradigms, but it’s a great puzzle: no one knows how to fit them together correctly. When we find out (strictly speaking I should say if’), it will be as a result of a paradigm that hasn’t shifted since the seventeenth century: theoretical structure expressed in the language of mathematics, built on and feeding back into an empirical base. And there will be real, at present unimagined consequences.You may say that’s naive or begs the ontological question. But I say it’s the best we’ve got. No amount of self-regarding talk about hermeneutics and postmodern science though it comes with a reference list as long as your arm to all the stars of critical theory’ will advance our understanding one iota. Whatever the world is, it isn’t like that, and Kuhn never really imagined it was.In spite of the impression I may have given, the book is worth reading and it isn’t difficult (some background knowledge of actual science would help). Read it for yourself; don’t believe everything people say about it.Note added: Some readers think that Kuhn was describing a process of successive approximation to truth, incorporating a smart new account of convergence. The point cannot be made too strongly that he was doing nothing of the sort. I recommend reading page 206 from which the remarks about really there’ were quoted. You don’t have to be a relativist and anti-realist to be a Kuhnian, but it helps.