The Power of Paradigms

It was the good Dr Phil who introduced me to that wonderfully insightful book by Thomas S Kuhn, The Structure of Scientific Revolutions. Kuhn showed that the progress of science has been largely discontinuous. Most scientists work within a generally accepted set of theories (which Kuhn termed a paradigm) and are largely content to make incremental additions to scientific knowledge within those confines without challenging the prevailing paradigm. Kuhn showed that the major scientific breakthroughs come from challenging the paradigms themselves.

There are many examples of such paradigms, but if you are unfamiliar with the term let me give you a simple example. Up until the sixteenth century, largely based on biblical texts, astronomers believed that the earth was at the centre of the universe and that the sun orbited around the earth. Because this was not the case, their models grew increasingly more complex to explain the movement of the planets. The Polish mathematician and astronomer Nicolaus Copernicus challenged this paradigm and in 1543 published De revolutionibus orbium coelestium (On the Revolutions of the Celestial Spheres). In this treatise Copernicus proposed that our solar system is heliocentric. Putting the sun at the centre provided a much simpler model. The change in thinking over the next century or two driven by this new concept was called the Copernican Revolution and stimulated many new discoveries.

Kuhn wrote:

“The very ease and rapidity with which astronomers saw new things when looking at old objects with old instruments may make us wish to say that, after Copernicus, astronomers lived in a different world. In any case their research responded as though that were the case.”

(Of course one of the champions of heliocentrism was Galileo. Unfortunately Galileo was tried by the Inquisition in 1633 and found guilty of heresy and forced to recant. But the Catholic Church quickly redressed their error and in 1992 magnanimously pardoned Galileo!)

It is easy to see that, even in modern times, it takes quite some courage to challenge the conventional wisdom.

The neuroscientist and Director of the Centre for Brain and Cognition, University of California, V. S. Ramachandran explains the process conventional scientists use to defend the status quo:

“One can speak of reigning paradigms – what Kuhn calls normal science and what I cynically refer to as a mutual admiration club trapped in a cul-de-sac of specialisation. The club usually has its pope(s), hierarchical priesthood, acolytes and a set of guiding assumptions and accepted norms zealously guarded with almost religious fervour. (Its members also fund one another, and review one another’s papers and grants, and give one another awards.)”

(Ramachandran is a brilliant researcher and great communicator. Some years ago he delivered the Reith Lectures on the BBC. These were very stimulating and insightful. They are worth a read if you can get hold of transcripts.)

Let us look at a more recent example of someone willing to challenge an accepted paradigm.

For decades it was believed that stomach ulcers were caused by stress, spicy foods and excessive stomach acid. But the Australian physician, Barry Marshall began to doubt this and pondered whether indeed ulcers might be caused by bacteria – specifically a bacterium called Helicobacter pylori. The notion was largely discounted by his peers. When he could not conclusively prove the connection Marshall took the drastic step of ingesting the bacteria and observing the effects on himself. When the symptoms of peptic ulcers then began to manifest themselves he dosed himself with antibiotics which duly cured him. Now one has to say that it takes a great deal of self-belief to proceed with such a course of action!

In 2005, the Karolinska Institute of Stockholm awarded the Nobel Prize in Nobel Prize in Physiology or Medicine to Marshall and Robin Warren, his long-time collaborator, “for their discovery of the bacterium Helicobacter pylori and its role in gastritus and peptic ulcer disease”.

That scientific progress is impeded by the refusal to challenge generally accepted beliefs is a common motif in the history of science. We saw above how prior to Copernicus the belief that the sun revolved around the earth was not challenged. The Bible related how the sun and the moon moved across the skies. To insist that the earth actually orbited around the sun was to challenge the literal truth of the Bible – a challenge, as we have seen, which landed Galileo in a good deal of religious hot water!

Lest you think this is an ancient problem, let me give you a more modern example. Let us take a look at the case of Alfred Wegener and the Theory of Continental Drift.

Alfred Wegener was the scientist who championed the Continental Drift Theory through the first few decades of the twentieth century. Simply put, his hypothesis proposed that the continents had once been joined, and over time had drifted apart. The jigsaw fit that the continents make with each other can be seen by looking at any world map. See for example how the continents of Africa and South America would fit closely together. Wegener’s ideas received a hostile reception from scientists in geology, geophysics, zoogeography and paleontology. Their reaction was so strong that after a time serious discussion of Wegener’s proposition ceased altogether.

As the geologist, R Thomas Chamberlain declared,

“If we are to believe in Wegener’s hypothesis we must forget everything which has been learned in the past 70 years and start all over again.”

He was right, and this of course is the nub of the problem. We have a strong vested interest in preserving beliefs that we have laboured hard to acquire and we tend to reject any evidence that threatens them.

The fit of the continents is so convincing even an unskilled observer can see it. Moreover the theory was supported by fossil evidence. For example fossils found on the east coast of Brazil were identical to those found on the west coast of Africa. But underlying the skepticism was the fundamental belief in the notion of terra firma – that is that the earth is solid and immovable. Wegener’s theorem only was finally accepted when plate tectonics were discovered.

Ramachandran, who I quoted above, insists that scientists need to assiduously pursue anomalies because even though they often lead to dead ends, the few that don’t serve to compel us to call into question basic axioms. He writes:

“Conformist science feels cozy, given the gregarious nature of human beings, and anomalies force periodic reality checks even if the anomaly turns out to be flawed.”

Without the use of such strategies we don’t have the incentive to question the fundamentals and thus challenge existing paradigms.

And of course, as the good Dr Phil has shown, the notion of paradigms is not the exclusive province of science. He has used the concept to also explain the process of cultural change in organisations.

Perhaps we should leave the last word to Kuhn himself.

“Paradigms are not corrigible by normal science at all. Instead as we have already seen, normal science leads only to the recognition of anomalies and to crises. And these are terminated not by deliberation and interpretation, but by a relatively sudden and unstructured event like the gestalt switch. Scientists then often speak of the ‘scales falling from the eyes’ or of the ‘lightning flash’ that ‘inundates’ a previously obscure puzzle, enabling its components to be seen in a new way that for the first time permits its solution. On other occasions the relevant illumination comes in sleep. No ordinary sense of the term ‘interpretation’ fits these flashes of intuition through which a new paradigm is born.”

3 Replies to “The Power of Paradigms”

    1. Thanks Geoff. I had a quick look at your friend’s blog site. I scanned his latest essay and it was very well written indeed.I am sure others in my readership would enjoy it also.

  1. Man made climate change is the latest accepted scientific notion and if it is not a new paradigm it is pretty close. You certainly have to be a very confident scientist to question it and your credibility is going to take a hit if you did. Fact or illusion is still uncertain in my mind but there is a multi billion dollar international industry based on this science and it is far from certain at present. Unfortuantely I think this paradigm if it is a myth will not be shifted for at least another few decades.

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