The Proceedings of The International Colloquium in the Philosophy of Science in London, 1965 , included papers by  two of the most influential philosophers  of science in the 20th century, Thomas Kuhn  and Karl Popper. Based on Kuhn’s theory of scientific revolution and Popper’s evolutionary theory of science with its process of falsification through testing, the conference included papers by several other participants as well, including J.W.N. Watson and P.K. Feyerband. The proceedings were published in Imre Lakatos’ and Alan Musgrave’s widely read  ‘Criticism and the Growth of Knowledge.’ (Cambridge Uni Press, 1970.)

In Thomas Kuhn’s book, ‘The Structure of Scientific Revolutions,’ (1962) Kuhn argues that when an area of science selects a scientific theory, the process is like a political revolution. For Kuhn, scientific revolution, like political revolution, involves a choice between two incompatible modes of thought, or ‘paradigms,’ in which the adoption of a new paradigm demands the destruction of the old.

While a paradigm prevails, its adherents are engaged in what Kuhn views as ‘Normal Science’ a process where research is about validation of the paradigm. So called ‘testing’ in Normal Science is not actual testing but instead, a puzzle solving activity involving the dominant paradigm’s anomalies or discrepancies. Essentially Kuhn sees this, not as problem solving, but as a test of the scientist’s own puzzle-solving ability: ‘in the final analysis, it is the individual scientist rather than the current theory that is being tested.’ ( Kuhn in L&M p 5.)

This process of normal or mature science continues until scientists become doubtful of the paradigm’s adequacy to explain the natural phenomena and a revolution occurs, Kuhn’s ‘Extraordinary Science,’ when a scientist experiences a paradigm-switch described by Kuhn as  ‘a relatively sudden, unstructured event like the gestalt switch.’ ( Kuhn, 1962. p121.)

Karl Popper does not agree with Kuhn’s view of ‘Normal’ and ‘Extraordinary’ Science, instead arguing that science is an evolutionary process in which one theory is superseded by another with more explanatory power, a new theory that also eliminates the difficulties of the previous theory. Theory evolution is a process of conjecture and refutation involving testing. Tests for Popper are the criterion of demarcation between science, pseudo-science and other modes of enquiry.

As Popper explains it, ‘In order to avoid speaking at cross- purposes, scientists try to express their theories in such a form that they can be tested: i.e. refuted, (or else corroborated) by experience.’  Karl Popper ‘The Open Society and Its Enemies.’ (1962. p 218.)  Other modes of assertion are unacceptable because they do not lend themselves to a replication of the process by which scientists have arrived at their findings and thereby are not open to testing and possibly falsification.. Under these conditions, Popper argues, the theory that provisionally prevails does so, not because of the persuasive power of a group, as with support for an ideology, but because of a theory’s power to explain and predict observable regularities of nature and withstand attempts to refute it.

Some papers. eg ‘ Popper, Kuhn and the Evolution of Science,’ by Pat Duffy Hutchison (Brock Review, 1995.) argue, as does Kuhn himself, the correspondences between  Kuhn’s and Popper’s views of science. I consider their differences ter be fundamental. I agree with John Watkins’ observation (L&M 1970. p 26) that Kuhn views the science community as an essentially closed society, intermittently shaken by collective nervous breakdowns followed by restored mental unison, and Popper’s view that the scientific community ought to be, and to a considerable degree  actually is, an open society in which no theory, however dominant and successful , no ‘paradigm,’ to use Kuhn’s term, is ever sacred.’


‘Thus we have the following clash; the condition which Kuhn regards as the normal and proper condition of science is a condition which, if obtained, Popper would regard as unscientific, a state of affairs in which critical science had contracted into  defensive metaphysics. Popper has suggested that the motto of science should be: Revolution in permanence! For Kuhn, it seems, a more appropriate maxim would be: Not Nostrums but normalcy!’ ( L&M. 1970. p28.)

In setting aside Popper’s demarcation-criterion fer science Kuhn advances his own, the verification process of normal science puzzle solving.( L&M  1970, p6.) claiming that  ‘ if a demarcation-criterion exists, it  may just be in that part of science which Sir Karl ignores.’  ‘To rely on testing as a mark of science ‘ says Kuhn, ‘is to miss what scientists mostly do’ ( Ibid, p10)

Irrespective of the sociology issue, hafta’ say, philosophically, Kuhn is on weak ground here. David Hume had already demonstrated that, as Socrates said before him, we cannot say that we ‘know’ anything, except perhaps, ‘I think therefore I am.’ ). Hume’s ‘black swan’ argument, amusingly described by the thanksgiving turkey’s error of logic, in Nassim Taleb’s  ‘The Black Swan.’ even stumped Bertrand Russell and the logical positivists. Like Einstein said, after Hume, no matter the build up of corroborating data, one counter example destroys yer theory. Popper recognised the tentative nature of our knowledge as per Hume, all that a scientist can ‘know’ about his theory’s dependability is whether it has continued to stand up against the only logically possible test of selection, the unequivocal test of falsification. We can eliminate unfit theories and select one which by comparison, so far, demonstrates its fitness to survive.

While scientists, flawed human beings like the rest of us, can fall under the spell of confirmation bias, there’s the salutory reminder from Richard Feynman, ‘First do not fool your self …bend over backward to present the weak side of yer theory.’ And if you do not, well the requirements of open society science-methodology ‘show yer data and workings,’ should find it for you. Seems ter me the Climate Debate with Mann et al and Steve McIntyre, shows the process working in spite of attempts by the Hockey Stick team, to protect their theory at all costs.

This serf considers that fer Kuhn’s theory ter be corroborated it needs to be demonstrated :

(a) that a switch from ‘normal,’ committed-to-a-paradigm-science, ter its revolutionary overthrow, is what takes place within the scientific community,

(b) that this change over is an irrational process, a sudden change to an incommensurable new paradigm and not, as Popper argues, a rational  selection of a theory with better explanatory power.

Ter (B) Or Not Ter (B)?

I’ll start with (b) and argue that in order to show that the process from one theory to another is not an evolutionary move to a theory with better explanatory power, but a conversion process, Kuhn had to justify his theory of the incommensurability of theories, which Popper calls ‘the myth of the framework.’

Say, while workin’ on this, I happened ter come across the following paper by Amitabha Palmer, which sets out very clearly and in language a serf understands, arguments that I consider refute Kuhn’s theory of incommensurability of theories. I post it in its entirety so will only briefly outline its claims.

Mission to Transition

At the heart of Kuhn’s revolutionary view of science is the view that paradigm shifts arise out of crises. ‘A growing group within a community of experts will call for the overthrow of a theory because of its inability to satisfactorily account for observations. In such situations –when one paradigm is adopted over another–the choice is not one that can be made by appeal to logic or evidence: it is made by social persuasion. A consequence of this view is that science is not a cumulative enterprise, rather it is a series of extra rational choices of one paradigm over another. The purpose of this paper is to put pressure on Kuhn’s argument that scientific revolutions necessarily  involve a choice between  logically  mutually exclusive theories.’ ( p2.)

The paper employs three arguments to critique Kuhn’s claim of incommensurability of theories, which Popper calls ‘the myth of the framework:’

(1) Argument from zombie Newton meets Einstein, and inter-theory communication.

(2) Argument from Fundamentally Similar Meaning

(3)  Argument from Epistemic Peers.

Argument From Zombie Newton And Inter Theory Communication.

In this section Palmer supposes that Newton comes back from the dead and meets Einstein just after Einstein had figured out his new physics. Would they be unable to  communicate because they refer to different paradigms?

Would zombie Newton be able to understand when Einstein speaks of mass, despite the possible Kuhnsian response that because their terms refer to fundamentally different things, meaningful debate is not possible? Palmer thinks that when Einstein speaks of mass, that in a limited way, regarding fundamental notions of mass they could communicate. Newton would at least have a general notion of mass no different from the lay general public today….

‘We can look at other fields of study today and see that intra-theoretic communication is quite common. Suppose there’s a room with cognitive scientists, psychologists, behaviorists, cognitive and AI theorists. Although all of these people work within different but related theories, it seems odd if they couldn’t understand each other if they were speaking about ‘beliefs.’ Concepts which are shared between different theories don’t seem to be so radically different such that (necessarily) there is no overlap in meaning to the point where meaningful dialogue is impossible.’ ( p3)

Argument From Fundamentally Similar Meaning.

‘Science attempts to measure fundamental aspects of the natural world. I do not mean to say that this is all that science does, but I think it fairly uncontroversial that this is a fundamental aspect of the activity of science. and  ‘humans — and  particularly scientists — have adopted certain conventions about how we ‘chop up’ the natural world. Among some of these aspects, we measure space, time, energy and mass.’

There are ways we go about measuring these qualities. Consider space for example, comprised of notions of length, width and depth.  In measuring length we may start with a length of string, but later might adopt a metal rod as our standard. How we choose to quantify a particular aspect of the natural world is in part conventional.

‘But there is also another aspect of quantifying that isn’t conventional — these are facts about the natural world and logical laws. No matter how I choose to measure length (and by extension space) it is a fact of nature that certain materials will be better measuring instruments than others … It is by appealing to these facts of nature that I choose my convention. A logical law will make so if I add two lengths together, their sum will not be greater or less than the total of the two length.’  ( p5)

This brings brings us back to what a Newtonian can meaningfully discuss with an Einsteinian. Although there is a dispute over whatever measurement convention should be adopted, they are both referring to the same fundamental aspect and facts of the world. It might be true that the Einsteinian convention of measuring mass as equal to E/c2 yields more consistent results. But both theories aim to quantify the same fundamental aspects of the world.’  (p6)

Argument From Epistemic Peers.

While semantic incommensurability may be true of the 17th century zombie Newton, Palmer does not consider this would apply to Einstein’s peers. By narrow focusing on the theories and principles of Newton and Einstein, Kuhn, ‘ excludes the important developments outside of and adjacent to Newtonian physics that allowed Einstein to develop his theory. After all, Einstein did not develop his theories ex nihilo. Quite certainly Einstein’s peers would have also been familiar with non-Euclidean geometry and have shared the knowledge of the advanced particle theory.’  (p6.)

From this fact these adjacent developments could act as bridges for Einstein to explain how to derive his theory in terms of theirs. ‘Presumably these new developments are what enabled him to make his own leap from Newtonian physics … it seems reasonable that by sharing his reasoning with epistemic peers, others could too.’ ( pp 6,7.)

Einstein’s epistemic peers having access to the same relevant advances as Einstein weakens Kuhn’s argument that choosing between paradigms cannot be decided by rational debate.

So let’s take a look at Kuhn’s other thesis:
(a) that  the switch from ‘normal,’  committed-to-a-paradigm-science ter its revolutionary overthrow, is what takes place within the scientific community.

Might (A)  Be Applicable?

John Watkins (in Lakatos and Musgrave , pp34-37.) challenges Kuhn’s contention with focus on the very first scientist to take up  a new paradigm, a  process Kuhn describes as  a ‘conversion’ or  paradigm-switch that is ‘ a relatively sudden and unstructured event  like the gestalt switch.’ (Kuhn, 1962 )  Watkins contends that a new paradigm could never emerge from normal science in the way Kuhn describes.

Watkins critically examines four contentions by Kuhn that underpin his theory of normal science and it’s revolutionary overthrow.

(1) The paradigm-monopoly contention. A paradigm brooks no rivals. A scientist, while under the sway of one paradigm cannot seriously entertain a rival paradigm.

(2) The no-interregnum contention.  There is little or no time between the end of the old theory’s reign over the scientist’s mind and the beginning of a new theory’s reign.

(3) The incompatibility contention. A new theory will be incompatible and indeed incommensurable with the old theory, which reinforces the paradigm -monopoly contention.

(4) The gestalt-switch contention  which  follows from the other three contentions.

Watkin’s argues from the above that the switch to a new paradigm must be regarded in Kuhn’s thesis as the same thing as his invention of a new paradigm, which Kuhn endorses  in ‘The Structure of Scientific Revolutions.’  ‘ The new paradigm, or a sufficient hint to  permit later articulation, emerges all at once, in the middle of the night, in the mind of a man deeply immersed in crisis.’ ( p89.)  And at the Colloquium Kuhn says that theories are ‘invented in one piece.’ (L&M. p35.)

Watkins finds this ‘barely credible on psychological grounds ‘and suggests historical counter-examples such as the Inverse Square law an important component of Newtonian theory  (which Kuhn regards as a paradigm of paradigms) that has a long evolution from Hooke, Kepler to Copernicus.

Against Kuhn’s instant paradigm contention, Watkins maintains that  ‘since it takes time to develop a potential new paradigm to the point where it may challenge an entrenched paradigm, heretical thinking must have been going on for a long time before paradigm-change can occur.” (L&M. P37.)

Regarding two descriptions of reality as rival alternatives, that is, logically that cannot co-exist, it is possible to make rational choices between them partly because it is possible to devise crucial tests, eg stellar parallax, star-shift etc. They cannot therfore be regarded as incommensurable.

From these arguments Watkins concludes that that a reigning paradigm does not hold such a sway over scientists’ minds that they are unable to consider it critically, that competing theories are not incommensurable, belonging to different universes of discourse but rival alternatives able to be critically appraised, and therefore the scientific community is not the closed society incapable of critical discourse claimed by Kuhn.


Kuhn defines science quantitatively as what the majority of scientists ‘do,’ which he describes as a verification process that is largely uncritical. Popper maintains that this is a state of non-science in which critical science has contracted into a defensive metaphysics. Only that lesser group practising science to a high standard involving the western tradition of critical investigation involving rigorous testing are doing science.

It is this western tradition of scepticism from Socrates through to Galileo, Montaigne, Feynman and Einstein , a qualitative distinction, that Popper sees as integral to doing science. Einstein  recognised the conjectural nature of science. He understood  that his own theory of relativity, like Newton’s theory, were not laws of nature but rather, conjectures about nature, each in their turn refutable. Einstein ‘spent the second half of his life looking for a theory that would subsume and supersede his own theory of relativity, in exactly the same way that he had superseded Newton.(BMp65.)

This process is easily perverted by behaviours and processes described by Bryan Magee in ‘Confessions of a Philosopher,’ by Nassim Taleb in ‘The Black Swan,’ and Professor Judith Curry, Climate Etc thread, ‘Has science lost its way? 01/12/13.


Philosopher Bryan Magee, who interviewed both Bertrand Russell and Karl Popper for his BBC series on the history of philosophy describes how Russell, regarded as the father of logical positivism, did not regard himself as one of them. Like Popper, and Einstein, Russell recognised that logical positivism’s process pf verification was illogical, that, following Hume, from no number of observations however large, can  any general conclusion be confirmed. We can never verify. Russell could only hope that ‘something less sceptical than Hume’s system may be discoverable.’ ( BMp130.)

Though stumped by Hume’s problem Russell still considered the central task of philosophy remained its traditional task of trying to understand the nature of reality and the limits of our knowledge. And while Russell, more than anyone, says Magee, developed new techniques of logical analysis, he never regarded the application of these new developments in logic as anything more than tools for philosophy’s main task. Bertrand Russell, as did Popper later, recognised the sterility of logic chopping , the puzzle solving of Oxford philosophy, as an end in itself, like the medieval scholasticism of the Middle Ages. (pp 84/5) Who cares how many angels can dance on the head of a pin?

Say, and while we’re on the subject of human fallibility, yer jest can’t ignore human propensity fer self delusion and confirmation bias, explored by Greek tragedians and Nassim Taleb. In Chapter 10 of ‘The Black Swan’ Taleb gives examples of our tendency ter look fer instances that confirm the beliefs we construct, a propensity  highly developed  in ‘experts.’ Taleb calls this the ‘expert problem’ or ‘tragedy of the empty suit.’ Taleb appreciates that KarlRaimond Popper, as he refers ter him, recognised this and made of scepticism a method with testability as its demarcation. Directives from guvuhmint bodies that  seek desired outcomes, like the IPCC brief to measure AGW  causes of global warming is an impediment to objective research fer various reasons, on of them financial. 😦

Judith Curry at Climate Etc has a thread, ‘Has science lost its way?’ ( 01/12/13) that raises some important issues regarding the ‘perverse incentives that do not serve  the societally- relevant applications of science. ‘Professor Curry does not think that science per se has lost its way but  that the Science/ Nature model and the way universities reward scientists are perverse incentives.

Michael Eisen, the author of the thread, discussed evidence of flawed papers being published in important journals and argues that: ‘The journals want the papers that make the sexiest claims. And scientists believe that the way you succeed is having splashy papers in Science or Nature – it’s not bad for them if a paper turns out wrong if its gotten a lot of attention.’

Michael Eisen is a pioneer in open access scientific publishing to replace the present model. He claims that: ‘The flaw in the publication model is that the drive to publish in a top journal  … encourages researchers to hype their results especially in the life sciences’. And unpaid reviewers ‘seldom have the time or inclination to examine a study enough to unearth flaws or errors.’

Here’s a comment on the thread, ‘Has Science lost it’s way?’ by RiHo08, (December1, 2013 @10.04 pm ) that serfs consider goes to the heart of  Popper’s qualitative assessment of ‘scientist’ or not.

‘Has science lost its way? To me the question is answered by noting whether the scientists have lost their way and with it, the science they represent. The scientist who lacks integrity has lost his/her way.

We as outsiders can judge a scientist’s integrity; hence judge whether the work is worth ascribing significance. And how do I decide if someone displays integrity? by their body of behaviors. That’s right, integrity is judged by people’s behaviors. Now there are some people whose behaviors I do not like, yet by what they choose to say, what they choose to do within the body of their work I am willing to look for other aspects; i.e., sharing information, acknowledging mistakes, errors or uncertainties that over time I begin to trust what is said and I am willing to acknowledge that the person is doing their work with integrity. It makes their work “believable” at least for the short run.

Science is relatively inert with regards to whether it is losing its way I think. Science is the process of inquiry and that process is use for better or not by the scientists doing such science.

It is the scientists that lose their way, and that is highly individual.’


The Road Not Taken.

Two roads diverged in a yellow wood,
And sorry I could not travel both
And one traveller, long I stood
And looked down one as far I could
To where it bent in the undergrowth.

Then took the other, as just as fair,
And having perhaps the better claim
Because it was grassy and wanted wear,
Though as for that the passing there
Had worn them really about the same.

And both that morning equally lay
In leaves no step had trodden black.
Oh, I kept the first for another day!
Yet knowing how way leads on to way
I doubted if I should come back.

I shall be telling them with a sigh
Somewhere ages and ages hence:
Two roads diverged in a wood, and I,
I took the one less travelled by,
And that has made all the difference.

Robert Frost.

‘The Road Not Taken’ is a poem where the speaker seemingly eschews the well travelled path but look again. Both paths are equally untrod … ‘but later with a sigh, I shall be telling  …’    Hmmm, confirmation bias. First do not fool yerself.