Or did he make it up? (Part – 3)

By : Niranjan Kambi, Department of Psychology, University of Wisconsin-Madison, USA

Here, take a moment to absorb and appreciate the rather “occult” nature of this interaction between matter without any contact and the sheer genius of Newton. He conjured up a force, which he called gravity or the force of gravitational attraction, to make sense of how stars, planets and galaxies moved in space. 

As Pirsig remarks in ZAMM, “Well, I predict that if you think about it long enough you will find yourself going round and round and round and round until you finally reach only one possible, rational, intelligent conclusion. The law of gravity and gravity itself did not exist before Isaac Newton. No other conclusion makes sense.”

I am sure it feels absurd to say that the law of gravity, indeed gravity itself, didn’t exist before Newton. However, when one sees it as a mystical force acting remotely between objects then the absurdity of the concept of gravity seems inescapable. In fact, Newton himself was embarrassed by his idea as he noted in his correspondence with Richard Bentley: “It is inconceivable that inanimate brute matter should (without the mediation of something else which is not material) operate upon and affect other matter without mutual contact…That gravity should be innate inherent and essential to matter so that one body may act upon another at a distance through a vacuum without the mediation of anything else by and through which their action or force may be conveyed from one to another is to me so great an absurdity that I believe no man who has in philosophical matters any competent faculty of thinking can ever fall into it. Gravity must be caused by an agent acting constantly according to certain laws, but whether this agent be material or immaterial is a question I have left to the consideration of my readers.”

To be clear, we are not denying the obvious observation that an apple falls from the tree to the ground or that our planet is revolving around the sun. However, the scientific explanation for these observations or facts – that there’s this attractive force called gravity and it behaves according to the law of gravity – was not around until Newton dreamed it up in the 17th century. Moreover, Newton’s law of gravitation survived not just because it was a fanciful thought from the mind of a genius but because it predicted and explained many of the observations physicists were puzzled by in his time, from the peculiar orbital motions of planets around the sun to why tides occur. In time, though, it was found that observations, like distortions in Mercury’s orbit, were not accurately predicted by Newton’s gravitational law. 

When this happens, scientists generally either modify the theory to fit the anomalous observation or reject it completely and devise a new theory.

To be continued… Next Week