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Thursday, 5 January 2012

On so called scientific knowledge – X

Karl Popper was able to add something of his own to Western Philosophy of Science. This branch of western epistemology is in effect concerned with making theories in order to show that Western Science is unique and is in general approaching the truth, Popper was of the view that Western science differs from other systems of knowledge in that Western Science develops trying to show the theories in general are falsifiable. In other words western scientific theories are formulated in such a way that they could be falsified. A theory that is falsified is thrown out according to Popper, and it is the business of Science to see that theories are not stagnant and replaced by other theories.

Now it was known that almost from the very beginning Newton’s Theory of Gravitation did not end up with “correct conclusions”. According to the theory the planets should be moving along fixed ellipses with Sun at one of the foci. The theory was falsifiable to a certain extent but no one knew which section or constituent of the theory had to be discarded and replaced with a new theory. The theoretical prediction was not observed as the planets did not move along fixed ellipses. They moved with an advance of the perihelion (the point on the ellipse closest to the Sun) and it was clear that the theory was not quite correct. However there was a problem as there were more than one constituent of the theory, one of them being the inverse square law, which said that particles in the universe attracted each other with a force inversely proportional to the square of the distance between them. Then another part of the theory said that the force between the particles is directly proportional to the product of the masses. The most important of the constituents of the Newtonian Theory of Gravitation was of course that the particles attract each other universally. This was beyond comprehension as it meant that a particle would exert a force on another particle instantaneously even if the particles were light years away.

During the time of Newton a force was supposed to be exerted on a particle or an object when it was either pulled or pushed. In other words in order to apply a force on a particle or an object one had to touch it either directly or indirectly with the help of a pole or a rope or some such object. Now in the case of Newtonian Gravitation a particle exerted a force (the so called gravitational force) on another particle without touching it. As we all know the Sun does not touch the Earth though there is supposed to be Gravitational Force between them. Newton’s contemporaries not surprisingly wanted to find the “rope” that connected the Sun and the Earth. Newton had no answer to this problem and all that he could say was it was action at a distance!

If Popper was correct in the sense that a falsified theory was discarded in western science then the scientists at the time of Newton or even after should have done away with the theory of gravitation and said that there was no gravitational force acting between particles. However, they did not do so until Einstein arrived in the patent office and not in a University at first and were interested in modifying other components of the theory. For example they toyed with the idea of modifying the inverse square law and said that the gravitational force between two particles is inversely proportional not to the power of 2 (inverse square) of the distance between them but to some other power such as 2.0000001 or 1.9999999. Modifying the inverse square law in that manner the scientists obtained a nasty differential equation that had to be solved but they managed to explain the advance of the perihelion.

Now the scientists should have adopted the modified theory discarding Newton’s theory as the former “explained” the “facts” better than the latter. However “rational” the scientists may claim to be they did not do so on aesthetic grounds! The original theory of Newton was beautiful than the modified theory with ugly powers such as 2.0000001. Feyerabend in his book Against Method gives a good account of this, and it should be interesting to know that western scientists are guided by aesthetics as well, and not confined to logic and observations of so called facts. Even today the symmetrical properties guide the western scientists in constructing new theories. Einstein was one of the best “beauticians” who did “facials” on theories. He was attracted to beautiful faces and he knew how to appreciate such faces at very close distances. He was interested in close action and never liked action at a distance, which he called spooky action at a distance and was ready to discard the so called Cosmological Constant which he had introduced and considered as a blunder, from the Theory of General Relativity the moment he got an opportunity. In his view the Cosmological Constant he had to introduce to make the Universe static destroyed the beauty (beautiful face or the expression) of the Theory of General Relativity. At Kelaniya we have been able to rescue the Cosmological Constant in a way, make it a cosmological parameter (variable) and make it a measure of the energy due to space (space-time if you wish) and bring the fifth “bhutha” “akasa” in line with the other four “bhuthas” “apo, thejo, vayo and pathavi”, in spite of great scientists, senior professors, so called academic heads of departments who would not touch a concept in Sinhala Buddhist culture, not to mention a “bhutha”, with a barge. (A paper making akasa and other bhuthas equivalent has been published in the Journal of Physical Science and Applications in its latest issue)

Thus the “rational” scientists in the west carried on with Newton’s Gravitation Theory even though they knew that the conclusions of the theory did not agree with the observations and that there was no way to explain a “force” between two objects at a distance apart. It implies that even if we are prepared to accept that “scientific theories” are falsifiable unlike other knowledge following Popper, it serves no purpose as the scientists are reluctant to discard falsified theories. If science carry on with falsified theories what is the big idea of constructing falsifiable theories in a Popperian sense? The irony is that while the scientists carry on with falsified theories most of them even today consider Popper’s falsifiable theory as the last word on Philosophy of Science. Peter Medawar, the Brazilian born English Immunologist was one of the better known scientists who adhered to Popper’s theory when the theory itself had been “falsified” in a way.

It was left to Thomas Kuhn who wrote his “The structure of Scientific Revolution” in 1962 to deviate somewhat from this Philosophy of Science. However, it has to be emphasised that he did not say that western science was not unique. All that he said was that western science progressed not by discarding falsified theories but through what he called revolutions. According to Kuhn in western science there are normal periods and revolutionary periods in science. Most of the scientists are no better than undergraduates who do experiments to verify existing theories and they are involved with normal science. Normal Science is not very exciting and it is problem solving within the same paradigm. According to Kuhn, it is during the Revolutionary periods that paradigms are shifted and theories are constructed within paradigms. The most famous paradigm shift is the Einsteinian paradigm that changed the views of the westerners on space and time. (To be continued)

Copyright Prof. Nalin De Silva