Kuhn’s predictions make prediction harder

Several decades ago I had a patient with complex needs that boiled down to what’s called “personality disorder”, combined with a low IQ. The problems presented as a great dependency on a weekly fix of doctor, on whom she could offload her many nebulous problems and vaguely uncomfortable feelings. She actually managed reasonably well on that.

At some point I lost touch as she drifted to a new medical crutch, but when I did get to see her again there was a significant difference, in that she’d been told, somewhere in the psychiatric referral system, that she was suffering from “depression”. Her problems were now all focused on that explanation, a very incomplete if not entirely incorrect one. I can’t say she was any more or less ill, but she was certainly less willing to attempt to deal with life issues herself, because the enemy was now a medical condition beyond her control.

In most cases of true depression, the diagnosis is a huge relief, as it defuses the overwhelming sense that ones own failure is the problem and enables one to fight the right enemy, through to recovery. But in this case, the patient sadly had little innate sense of self-worth to recover, and so the medical “knowledge” simply added to her load. It certainly changed, quite radically, the nature of the problems she had.

I felt a little of that in reading Thomas Kuhn’s indispensible book on The Structure of Scientific Revolutions. It has cast a new and essential light on the history of science, and on the way it actually works as contrasted to the textbook myth. So it has undoubtedly earned its reputation as a “game changer”. But by revealing what was previously an unselfconscious set of processes, it has changed not only the understanding of “paradigm shifts” in science, but like my patient’s diagnosis of depression, probably the nature of any future scientific revolutions in themselves. There is a big difference between feeling ill, and sticking your tongue out at the mirror in case you might be. As in quantum physics, observing a process alters it.

Nowadays, especially in the context of blogs like this, the big Kuhnian question is whether Neodarwinism is in the process of undergoing a paradigm shift, or not. In terms of diagnostics, it’s worth remembering that in Kuhn’s book Darwinism is treated mainly as an example of a revolution back in the day, and no questions are raised about its own present status.

But I would have to say that, according to the various criteria Kuhn lays down, Michael Denton was being no more than descriptive when he called Neodarwinism “a theory in crisis”, which is a terminus technici in Kuhn rather than a criticism. To Kuhn, all theories eventually reach a state of crisis, pending their replacement, so it would be surprising if Neodarwinism should be an exception. The only question is whether that time is at hand or not.

Several of Kuhn’s markers are, as far as I can judge, in place. For a start there is without doubt widespread questioning of whether the old paradigm is adequate from within the scientific community itself. That shouldn’t need too many examples, but one big one is ENCODE, which is certainly raising big questions and contriversy, if the number of aggressive edits on Wikipedia is a clue.

A second Kuhnian marker is also commonly cited, and that is the addition of “epicycles” to account for anomalies in the paradigm. An example of that might be convergent evolution, which isn’t especially well-accounted for by randon variation and natural selection (or by any other mechanism as yet) but is regularly used to explain surprising non-homologous similarities, thus making the surprise seem normal.

A third of Kuhn’s markers is the multiplication of variants of a theory within the paradigm. Perhaps the uneasy truce between adaptive and neutral evolution, or gradualism and punc eek,  would illustrate that, but also referenced in the book is the phenomenon of different specialities developing distinct understandings of the same theory, which certainly appears to be the case, from the mutual accusations of failure to understand the theory of evolution between molecular biologists, evolutionary biologists, population geneticists, palaeontologists, and so on.

A fourth feature to which he points is the tendency for the underlying philosophical foundations of a theory to be examined more around the time of a paradigm shift. That too appears to be the case with current evolutionary theory, as a number of the dissidents revisit the nature of causality in Goethian or Aristotelian terms. By the same token, one might find more professional philosophers questioning the theory on philosophical grounds as opposed to assuming its truth, as before. Pigliucci and Nagel come to mind.

Lastly Kuhn points to the development of a number of rival theories which, before a paradigm change, all fail to win the day because they do not have sufficient explanatory power to displace the original theory. The plethora of newly proposed mechanisms for evolution seems to fit that bill – the wide variations, for example, in the theories of those challenging the theory from within (such as the Altenberg 16 and the Extended Evolutionary Synthesis) or more consciously from the outside (such as the Third Way, apparently now becoming known as the Oxford 50, or even Intelligent Design, whose call for a change in science is probably more radical than most in its rejection of naturalism). It could be that one of these will prevail, but on historical precedent it’s more likely that some young scientist will propose an as yet unforeseen principle that unites most of the phenomena accounted for by Neodarwinism with all, or most, of the disparate contenders.

So far then, in my view, Kuhn would regard twenty-first century Neodarwinan evolutionary theory as being, under his criteria, in crisis in the sense of showing the relevant signs of awaiting a new paradigm. You may or may not agree, but that’s not my main concern here, for Kuhn’s book deals with theories in retrospect, and everyone will know soon enough if evolution does undergo its own revolution. No, what occurred to me as resulting from his thesis is that, unlike any previous situation is science, everyone is now fully aware of Kuhn, and his name is constantly dropped with respect to evolution – Michael Denton being just one, already mentioned, example.

How might such a sense of self-consciousness of possible change play out? I somehow doubt it would result in the easing of the wheels of change. Kuhn points out both the negative effects of resistance to change (the diehards refusing to accept new evidence and so on), and also the positive effects of such resistance, in maintaining a working paradigm against a descent into anarchy until there is something better to replace it. The fact is that those with vested interests, whether emotional, professional, financial or political, in an old paradigm will not have those motives much altered by reading that they are normal, in history and philosophy of science texts like Kuhn’s. Quite a few will, in all probability, reject those texts altogether as nonsense simply because they cut too close to the bone. That may account in part for the strong thread of anti-philosophical and anti-historical sentiment in the hard biological sciences, justified by those other disciplines not being hard sciences.

Others may decide that though scientific paradigms do undergo revolutions, their particular theory is too valuable to be allowed to “succumb”. In other words, the realisation of threat, in a manner that former generations of scientists lacked, might lead to more organised and desperate measures for self-defence. I just wonder if some of the experience of outright hostility from “the establishment” expressed by so many of those with alternative views on evolution might result from such entrenchment. If such a thing exists, it is likely to be more bitter nowadays simply because the forces involved are so much greater in science than ever before. Spats between private scholars in Victorian times must surely be on a different scale from our Big Science, supported by Big Universities, Big Government and Big Media, all wielding Big Money. Paradigms have roots extending far beyond science itself nowadays.

Conversely, whereas in former times dissidents would say, “There’s something inadequate about the old theory – here’s a new one,” nowadays people are, perhaps, aware that they are trying to shift a paradigm. Is that healthy or unhealthy for the progress of science? I’m not sure, but I suspect it alters the dynamic quite markedly. One might be reminded of those leftist student politicians of the sixties who were perceived as simply protesting for their views, but were in fact following a particular theory of how to subvert the body politic.

One criticism heard about those who see weaknesses in the Neodarwinian synthesis – or in associated theories such as hypotheses about the origin of life – is that one cannot criticise a theory without providing a replacement. I was interested to see that Kuhn refers to that very situation, suggesting that scientific critics of a theory will always be seen as “bad workmen blaming their tools”. He even suggests that some workers, no longer content to work within an existing theory but unable to come up with a better, leave the field altogether in disillusion. But Kuhn does not say that critics of a theory ought to provide a replacement, but rather that this is what tends to happen in fact. In order to continue doing their science, even dissatisfied scientists will continue to work within the existing theory until (perhaps in some cases with a sense of relief) they see its replacement arrive.

When a theory is in crisis, then, one would expect a proportion of scientists to be living with a degree of cognitive dissonance rather than the far more unsatisfactory and unproductive experience of working without a theory, which really means the impossibility of working at all. I hadn’t considered such psychological inevitabilities before reading the book. There is no mileage in a working scientist renouncing a time-expired theory whilst it is still the only game in town. In any case, Kuhn points out that most “normal science” is the filling in of the details of a theory’s application, so people who ask big questions about the theory itself are always in a minority.

On the other hand, note that the motivations for such attitudes of “working with the paradigm for lack of a better” are essentially professional. If one wants to stay in a science, one has to work with the prevailing theoretical framework unless one seriously believes one is on to something new. In that sense, scientists (as professionals) simply can’t criticise a theory without coming up with a replacement. I identify with that from my professional career in medicine. I had doubts about some of the basic assumptions of conventional medical practice then, and even more now I am several years distanced from it. But there were all kinds of reasons, practical and psychological, for not abandoning the usual professional framework, for there is no other apart from non-professional frameworks.

However, that’s not true for the non-professional outsider, who is in one sense advantaged over the professional, even whilst lacking in-depth working knowledge (cf Michael Polanyi’s Personal Knowledge) of a theory. An observer can afford to be agnostic in a way the professional cannot. He has no obligation to replace a deficient theory with a better, but is at liberty to say “a plague on both your houses” and play the field of possibilities. Even that role may have altered post-Kuhn, as science has become, in the Internet age, something on which the public has both a big stake (through taxes etc) and a bigger say than before – witness sociologist Steve Fuller’s concept of “Protscience“.

And so even if Neodarwinism turns out to be a genuine Kuhnian case of “a theory in crisis”, the very knowledge of the theory of paradigm shift may mean that the outcomes are as unpredictable as ever they were in earlier ages. Maybe Neodarwinism is set to continue to be as “certain as the law of gravity” for a long time to come.

On the other hand, there seem to be some recent murmurings even about the fundamental nature of gravity.

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About Jon Garvey

Training in medicine (which was my career), social psychology and theology. Interests in most things, but especially the science-faith interface. The rest of my time, though, is spent writing, playing and recording music.
This entry was posted in History, Philosophy, Politics and sociology, Science. Bookmark the permalink.

6 Responses to Kuhn’s predictions make prediction harder

  1. Avatar photo GD says:


    I find one aspect of Darwinian evolution (as a paradigm) may differ somewhat from the history of conventional scientific paradigms, in that it seems “driven” by acrimonious and often bitter arguments that are grounded in areas beyond the boundaries of biology. This is because atheists and some theists have invested heavily in what they perceive as changes in the world outlook of people. For many, Darwin has provided justification for belief in materialism, and/or for rejecting any belief in God. It is this that underpins the desire to maintain Darwin “at all costs”, so to speak.

    On the scientific side, an interesting paper provides a clue to the non-biologist, of the immense complexity faced by workers in the bio-sciences, is by S. Franklin, T. M. Vondriska, “Genomes, Proteomes, and the Central Dogma”, Circ Cardiovasc Genet, 2011, pp 1-9. The following quote gives a flavour of this:

    “The past decade, however, has witnessed a rapid accumulation of evidence that challenges the linear logic of the central dogma. Four previously unassailable beliefs about the genome—that it is static throughout the life of the organism; that it is invariant between cell type and individual; that changes occurring in somatic cells cannot be inherited (also known as Lamarckian evolution); and that necessary and sufficient information for cellular function is contained in the gene sequence—have all been called into question in the last few years.”

    Once again, I use this paper because it is another attempt at defending Darwin, this time by trying to extend the central dogma to include other observations and hypothesis (the more the merrier??!!)

    I have been fascinated by the simplistic belief in biology, in that the genome is linked to the phenotype (actual biological entity) in a linear fashion – yet this is the very basis for claiming links in a descendent from some “common” entity that existed in a sci-fi past (i.e. a % is similar or the same between species).

    • Avatar photo Jon Garvey says:


      Your last four paragraphs, in the context of the “Kuhnian” flavour of the OP, seem to confirm the loss-of-certainty/defence/attack features he describes.

      The first paragraph adds another distinguishing feature which, I think, makes for a unique situation. For whatever reasons (and I think they go back to the original response to Darwin by the Victorian reading classes, who were eager for a non-teleological explanation or everything) Darwinian evolution has become a crucial and iconic point for deciding the kind of universe we live in.

      One could argue that Galileo’s challenge to the Church was similarly a threat to a worldview, but it was much less so, firstly because many even within the Church were unhappy with the broadly Aristotelian paradigm that had (after all) been adopted into theology rather than being its basis; and secondly because many could see that heliocentrism was a minor issue biblically as well as theologically.

      Additionally, Galileo and his fellow Copernicans were trying to change science, not society at large. Huxley and his modern followers had a more aggressive agenda.

      But it’s a lot harder to argue for a fortuitous process once non-linear causation gains a foothold, whether from defenders or attackers of the paradigm. One is forced to explain a totality (and hence a teleology) rather than account for change piecemeal.

  2. pngarrison says:

    To clarify a couple of things.

    No one who has any chance of having an influence on how things turn out thinks that evolution didn’t happen. And yes, this means that Dembski and Meyer will have no influence.

    Also, the “central dogma,” Crick’s expression, has nothing to do with evolution. It was the assertion that information is expressed from nucleic acids to protein sequence. Protein sequence can’t be read backward to form nucleic acid sequence. No one has ever produced any evidence of “reverse translationase,” and it is extremely unlikely they ever will. It would take something as complicated as a ribosome to do it and anything that impressive would have been noticed long ago. It’s also hard to think of any reason that it would occur.

    Also, the significance of ENCODE has been and is still grossly overestimated by those desperately looking for help for their point of view. The ENCODE guys, for reasons known only to themselves, decided to hype their project by declaring that it obtained revolutionary results concerning the function of the genome. They “achieved” this by simply redefining function is a rather silly way, as any piece of the genome for which you could find any evidence of biochemical activity, even if only protein binding or transcription of RNA which is immediately degraded so that it is present at far less than one copy per cell. Any fragment of DNA that you stick into a cell will trigger biochemical activities on it. That means nothing about whether it will have any effect on cellular function.

    It has been suggested that the money spent on ENCODE could have been spent far better on smaller projects that were designed to ask specific questions about specific aspects of genome function in particular cell types under particular conditions. I suspect that it true. The specific studies are being done anyway, and a massive data gathering exercise like ENCODE will only help that in rather general ways.

    • Avatar photo Edward Robinson says:


      Let’s set aside the question of how the phrase “central dogma” is properly used, and talk about what people are driving at when they speak (however inaccurately) about challenges to the “central dogma.” I think that what they are driving at is an attack on the old idea (going back to Weismann) of the genome as a “read-only-memory” store which sits in Olympian aloofness from organismal activity. Here is the Wikipedia summary concerning Weismann (not that I count Wikipedia as any great source of accurate science, but I’ve seen essentially the same account in many other places, and this one is handy):

      “The effect is one-way: germ cells produce somatic cells and are not affected by anything the somatic cells learn or therefore any ability the body acquires during its life. Genetic information cannot pass from soma to germ plasm and on to the next generation. This is referred to as the Weismann barrier.[3] This idea, if true, rules out the inheritance of acquired characteristics as proposed by Jean-Baptiste Lamarck.[4]

      The idea of the Weismann barrier is central to the modern evolutionary synthesis…”

      So even if Weismann’s “central dogma” (so to speak) was not in itself a statement of evolutionary theory, but only a statement of the relation between germ cell and body, it still had evolutionary implications; i.e., one would expect that the genes would be altered only by violence or accident of some kind (radiation, chemical assaults, etc.), never under any circumstances by the internal activity of the organism itself. So evolutionary theory would then speak of “random mutations”, accidental events not directed by the organism, which alter the genome and hence the next generation of the organism; evolutionary theory would eschew any thought that the organism might in some cases modify its own genome.

      Now, if I understand the challenge to this aright, many biologists are now saying that organisms do sometimes alter their own genomes, in response to environmental stresses, etc. That is, there really are some “Lamarckian” events; the flow of information between genome and organism is not always one-way.

      I am not saying, and I don’t think these biologists are saying, that proteins produce nucleic acids by a sort of reverse genetic code in a literal reversal of protein synthesis; rather, I think what it being said is that the old idea of the serene isolation of the genome, and the impossibility of any life-experience altering the genome, is no longer tenable.

      I am not competent to discuss the evidence and argumentation here, but here is an article which summarizes this point of view, and appears to be written by someone with not an insignificant grasp of the technical literature, and not an insignificant grasp of the subject-matter:


      Would you say that this article is complete nonsense, that none of it is true? Would you maintain that it has no relevance to evolutionary theory?

  3. Avatar photo GD says:

    The paper I sited is very clear on the central dogma, and they add, “…Because of its simplicity, the central dogma has the tantalizing allure of deduction: If one accepts the premises (that DNA encodes mRNA, and mRNA, protein), it seems one cannot deny the conclusions (that genes are the blueprint for life). As a result, the central dogma has guided research into causes of disease and phenotype, as well as constituted the basis for the tools used in the laboratory….. ‘

    Unless you can show this statement is erroneous, I cannot see why anyone would debate the matter, or offer some sort of defence.

    The paper goes on to agree with your basic assertion, that evolution (whatever that term may now mean) is the current paradigm. I have not suggested otherwise.

    They continue however, with comments that seriously question the reasoning, which to my non-biological view, amounts to denying a straightforward (linear) connection between genomics and the end result we would consider (phenotype, or complete species).

    The questions posed strike at the fundamentals of Darwinian thinking, and the basis for common descent. If you can prove a direct link between all of these genetic sequences (and their apparent history), and each and every species considered, then, and only then, would a Darwinian have good grounds to make the claim that a sufficient percentage in the similarities of the genetic sequences constitute scientific proof for their hypothesis of common descent (although the present data supports diversity and variation, because this does not require the direct, or linear link, demanded by common descent). If they cannot (as this paper indicates), they lack the solid scientific ground for their assertion. Note I am not questioning the data, nor suggesting biologist failed to provide scientifically acceptable experimental or empirical ‘evidence’. I am stating the obvious, in that workers in this field openly question such a direct link, which is clearly needed for the current arguments for common descent.

    I have also previously referred to the paper by Koonin (another Darwinist) who states, “… Evolutionary-genomic studies show that natural selection is only one of the forces that shape genome evolution and is not quantitatively dominant, whereas non-adaptive processes are much more prominent than previously suspected.” This scientist has proposed a ‘forest of trees” instead of a single tree of life proposed by Darwin.

    I have purposely selected papers which support the current paradigm, and have avoided arguments put by your opponents (creationists, and what have you), simply to show that good science keeps showing flaws/inadequacies/lacks (or any other synonyms), and I had noticed this since my student days, when we were told that Mendel had finally sorted out the difficulties in Darwin’s semantic theory.

    I think Jon is making a useful point in this post, regarding the usual resistance to criticisms of any paradigm in science. I am making an additional point, in that people are more adamant regarding Darwinian evolution, for non-scientific reasons.

  4. Avatar photo Jon Garvey says:

    It may be that ENCODE is an example of how Big Science doesn’t necessarily make for Good Science, but in the context of Kuhn that’s irrelevant: it provides a pre-packaged example of dissent against a governing paradigm, quid erat demonstrandum. The phrase “for reasons known only to themselves” gives me pause for thought – their reasons are either scientific and published, or non-scientific and subversive… and the same may be said for the publications of those who attribute dark motives to such a large and distinguished team – either way we see science being shaped by more than scientific considerations.

    Whether any replacement for Neodarwinism would be evolutionary is, of course, unpredictable before the event, or it wouldn’t be a revolution. But it’s likely it would be broadly so, since Darwin came on the back of maybe a century or more of evolutionary ideas. However, the “Kuhnian” question isn’t about the overturning of evolution as change over time, but of Darwinian theory (random variation + NS), just as Newtonian gravitational theory wasn’t disputing that things fell, but was claiming that there was an occult force acting at a distance that made it happen (which had been a totally “unscientific” concept for a century or so under the reigning corpuscular paradigm, which had ousted Aristotelian science in which occult forces acting at a distance were deemed legitimate). All this is spelled out in Kuhn.

    It could be that Neodarwinian theory would be subsumed under any new theory that, de eventu, replaced it, as Newton’s gravitational theory is often said to be a special case of relativity under restricted conditions. But Kuhn suggests the latter view is misleading – the changes needing to be made to Newtonian theory to make it compatible with relativity actually change the theory, and more significantly Newtonian theory is no longer a useful research paradigm, but is only “useful” as an approximation for, say, astronautics. He compares geocentric theory, which is still used in the teaching or earthbound navigation, but cannot be properly viewed as a subset of heliocentrism.

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