Tuesday, May 07, 2013

Flawed Idea

Prof. Thomas Kuhn

One of the most influential books ever written about science is Thomas Kuhn’s The Structure of Scientific Revolutions.1 This book launched the modern version of the Philosophy of Science and frankly a lot of the Post-Modernist views of Science.

In it Prof. Kuhn postulated that Scientists are welded to paradigms that are in essence an all-encompassing view about how reality or a given section of it operates. When Scientists find anomalies they tend to ignore them until the anomalies pile up and a new alternative paradigm is created to explain the phenomena. Scientists do not work by patiently accumulating evidence but by collecting data that “fits” a particular paradigm.

Also how well a paradigm fits the observed facts depends on the questions asked by the Scientists and the nature of the questions molds the answers that the Scientist finds.

Thus advances in Science occur has paradigm shifts, in which Scientists radically change their basic assumptions of how a particular set of phenomena work or operate and this in term molds the questions that they ask. Thus the advance of Science is nothing more than the changing of one or more paradigms of other newer paradigms.

In this view the reason for new paradigms is not simply the existence and discovery of anomalies, because those can be and usually are simply explained away but changes in the world in which the Scientist lives gives rise to new questions and attitudes that led some to question the old paradigm the result being that the old one is viewed has not quite good enough. This in turn leads to the creation of new paradigms, one or more of which are accepted and overthrow the old paradigm because they satisfy the new questions and new attitudes of the Scientists.

The new paradigm is in effect more aesthetically pleasing because it now better fits the mental world of the Scientists in question and it explains the anomalies that arise when new questions are asked of the old paradigm. Many of these questions would not be asked of the old paradigm because in the mental world of the Scientists who believed the old paradigm such questions were not even conceived of or were simply deemed irrelevant.

The interesting point about the above view of paradigm shift is that there is no room in it for evidence producing a shift; instead the “real” reasons are aesthetic / cultural / political. Thus the gradual accumulation of evidence plays no role in producing change in Science instead it is macro shifts in world views that produce the changes. Other than that Scientists simply find stuff that confirms the current paradigm, and in fact they are ideologically welded to the current paradigm(s).2

Perhaps the most surprising aspect of this view is that it seems to regard the view that Science gets us closer to the truth has illusionary. In Prof. Kuhn’s view newer theories / discoveries don’t really get us closer to the truth than any other. All that is changed is that the new paradigms answer different questions. Science doesn’t get us any closer to the truth because the mental worlds of each different paradigm are not comprehensible to each other and therefore cannot be compared. So each paradigm is equally “right” and equally “wrong”.

In all the acceptance of a new paradigm means the exchange of one world view for another so that the previous world view / paradigm cannot even be understood anymore. They are incommensurable In fact everything changes with a new paradigm including how the paradigm is judged and tested. The result is an impossibility of comparison, because how we judge and test has changed so radically.

Of course this goes very well with Post-Modern doctrines about how we “really” can’t know anything and that all is discourse and that reality is basically a mental image.

Prof. Kuhn did not shy away from the radical implications of what he said. In effect he did deny that “Science” did in fact tell us about the reality that was out there. In Kuhn’s view each paradigm was just has good as any other paradigm and the reasons why one paradigm replaced another had less to do with how well one or the other described reality than the biases, and ideological perceptions of the Scientists as evidenced by the questions they asked and deemed important.3

Kuhn viewed Scientists as basically people who followed a collective paradigm which quite properly they did not question because to do so would shake the whole paradigm and hence the whole mental world on which the Scientists believed in.

Thus according to Paul Feyerabend Kuhn’s view of Science is that science must:
…restrict criticism, to reduce the number of comprehensive theories to one, and to create a normal science that has this one theory as its paradigm. Students must be prevented from speculating along different lines and the more restless colleagues must be made to conform and “to do serious work”. Is this what Kuhn wants to achieve? Is it his intention to provide a historico-scientific justification for the ever growing need to identify with some group?4

Thus like much modern day Post-Modernism the implicit authoritarian conservatism is not very well concealed. It is also interesting to note the contrast with Karl Popper’s notion of Science as falsifiability i.e., questioning and experimentation not paradigm building.5

Of course one obvious rejoinder to Kuhn’s contentions is that if it is largely in the minds of Scientists just how do we do anything with Science?  After all a nuclear reactor is pretty good evidence that the Theory of Relativity describes the real world pretty well and no amount of talking about incommensurable paradigms will change that fact.

To quote one observer:
Kuhn’s view of scientific progress would leave us with a mystery: Why does anyone bother? If one scientific theory is only better than another in its ability to solve the problems that happen to be on our minds today, then why not save ourselves a lot of trouble by putting these problems out of our minds?6

And of course what is downgraded in Kuhn’s view is the role of experimentation in Science. In Kuhn’s view experimental results did not generate the need for new paradigm’s instead they usually only confirmed the old paradigm(s), and any anomalies were explained away. This being case experimental results “should” only serve to refine the current paradigm. In fact only paradigm shifts could result in any fundamental advance in Science. Although give Kuhn’s views that paradigm shifts never “really” get us closer to the “truth” than what is the point? Apparently it is pleasing the Aesthetic and ideological biases of Scientists and the world they live in. Thus as one critic has said:
And it is just these conclusions that have made Kuhn a hero to the philosophers, historians, sociologists, and cultural critics who question the objective character of scientific knowledge, and who prefer to describe scientific theories as social constructions, not so different from democracy or baseball.7
In so far has Kuhn has aided and abetted this type of no-nothing obscurantism he has done us all a disservice.

Now to the real question which is does Kuhn’s view of how Science actually changes by paradigm shifts with each different paradigm being incommensurable with the other in fact true?

As one writer has described Kuhn’s basic notion that Kuhn:
…describes the history of science as a cyclic process. There are periods of “normal science” that are characterized by what Kuhn sometimes called a “paradigm” and sometimes called a “common disciplinary matrix.” Whatever you call it, it describes a consensus view: in a period of normal science, scientists tend to agree about what phenomena are relevant and what constitutes an explanation of these phenomena, about what problems are worth solving and what is a solution of a problem. Near the end of a period of normal science a crisis occurs—experiments give results that don’t fit existing theories, or internal contradictions are discovered in these theories. There is alarm and confusion. Strange ideas fill the scientific literature. Eventually there is a revolution. Scientists become converted to a new way of looking at nature, resulting eventually in a new period of normal science. The “paradigm” has shifted.8
Well the fact is there is a lot wrong with Kuhn’s view of Science.

First the argument that Scientists cannot shift back and forth between different paradigms is simply false. Scientists do it all the time and frankly so do Social Scientists. The classic example is Anthropologist who switches between biological and cultural ways of looking at the same phenomena.

Also the idea that paradigm replacement is complete replacement and that thinking in both is impossible is wrong. The example that Kuhn gave of the replacement of Newtonian physics with Relativity physics is a particularity bad one. After all once Physicists had accepted Relativity did they cease to understand Newtonian physics? No they did not.

In fact taking High School physics today you will be taught both Relativity and Newtonian physics. Relativity has not replaced Newtonian physics it has merely supplemented it.

Thus the theories of Maxwell that lay out the physics of how we understand electro-magnetic forces have not been replaced by a new paradigm.

In fact it appears that much of the time the advance of Science is in evolutionary small steps not quantum leaps via paradigm shifts. The Social sciences especially are examples of this sort of bit by bit change.  

As mentioned above much of past Science remains valid it is recognized has incomplete not simply “wrong”. Thus the advances in geographical and geological knowledge have not been in the form of massive paradigm shifts but the gradual accumulation of data. Thus uniformism and catastrophism in geology were not incommensurable paradigms but simply different views of the phenomena and both at least partly valid.

So if Kuhn’s view of how Science actually works is over skeptical and empirically wrong in many respects just where did it come from?

It is suggested that Kuhn took a historical example of a paradigm shift and then decided it was typical. In this case it was the replacement of Aristotelian physics with Newtonian physics. Kuhn was aware that Aristotle’s physics was considered almost totally wrong right down the line and Newtonian physics is quite different. So Kuhn assumed that paradigm shifts in Science and change in Science generally was very much like the shift from Aristotle’s physics to the physics of Newton. The result being that the questions and assumptions of each of the two paradigms were in fact  incommensurable. However if you thought like a Aristotelian Aristotle’s physics still made sense.9

Of course this had one problem the reason that Aristotle’s physics held sway for so long was because of a lack of experimentation and dogmatism. Once experimentation became routine it was bound to fall apart.

To give just one example Aristotle assumed that heavier objects fell faster than lighter ones. Simple experimentation would have demonstrated that this was simply wrong. But dogmatism and the idea that this was “common sense” kept the idea around along with lack of experimentation.

Also Aristotle did not know of and in fact implicitly rejected the notion of inertia. Thus in Aristotle’s physics an object to keep moving had to be continually acted upon. In fact the idea that objects will keep doing what they are doing, including moving, until acted upon is simply true and there are an abundance of experiments to show that this is so.

So it appears that Kuhn’s inspiration for his notion of paradigm shifts is an unusual one in the history of Science and further it appears that it wasn’t just because world views or paradigm(s) shifted that it was eclipsed but that it was largely simply wrong. Aristotle physics would only still make sense if you ignored the data and experimentation.

This being case Kuhn’s idea is in the end seriously flawed.


1. Kuhn, Thomas, The Structure of Scientific Revolutions, Third Edition, University of California Press, Berkeley CA, 1996. (Original Edition 1962.)

2. IBID, and especially pp. 43-51, 111-135.

3. Footnote 1.

4. Feyerabend, Paul, quoted in Fuller, Steve, Kuhn vs. Popper, Icon Books, London, 2006, pp. 193-194.

5. See Fuller.

6. Weinberg, Steven, The Revolution that Didn’t Happen, New York Review of Books, October 8, 1998. I used the electronic edition.

7. IBID.

8. IBID.

9. IBID.

Pierre Cloutier

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