Jethalal S. Zaveri
Prof. Muni Mahendra Kumar
As we have seen, Philosophy and Science were not separate until the first half of the seventeenth century when Rene Descartes based his view of nature on a fundamental division into two realms - mind and matter. The Cartesian division helped the scientists to study the physical universe as an independent objective reality. And they treated the material world as a huge machine composed of different objects. It was Isaac Newton who constructed his mechanics on its basis and his laws became the foundation of the classical physics. From the second half of the seventeenth to the end of the nineteenth century, scientific thinking was very largely dominated by the Newtonian model of the universe, which supported all of science as well, as Natural Philosophy for almost three centuries.
Newton was the first person to discover "Laws of nature" which unify many aspects of common experience. Newton's Laws of Motion were, in fact, based upon sound experimental evidence and nothing else. They predict and depict events which are simple to understand and easy to picture, because they pertain to ordinary objects of daily experience. Besides the laws of motion, Newton's great contribution to science was the 'law of gravity' - a remarkable Natural phenomena, though it is generally taken for granted. It is the same force, which pulls objects downwards and also keeps the celestial bodies like the moon and the planets rotating in the orbits. The laws of motion not only give us a foreknowledge of eclipses, seasons etc., but we can also know precisely where the moon will be in relation to the earth, and the earth in relation to the sun at any given moment. Without Newtonian physics, the space-programmes might not have been possible.
The stage of the Newtonian universe was
- the three dimensional absolute space-"always similar and immovable" and
- absolute time, a separate dimension-"flowing uniformly without regard to anything external".
Material particles (actors) or mass-points-small, solid and indestructible objects, out of which all matter was made - moved in this absolute space, filled with ether (medium of motion), strictly obeying the laws of motion in respect to the absolute time. It can be seen that this model was' not very much different from that of Greek atomists. The important difference between the Democritean and Newtonian atoms is that the former were moved by external forces, which were assumed to be of spiritual origin, and therefore, were fundamentally different from matter while in the case of Newtonian particles, the moving force acting between them is an innate quality of matter, depending upon the mass and the mutual distance of the particle. It is the force of gravity.
Physicists up to the 19th century firmly believed that the universe was indeed a huge machine working in accordance with the Newtonian equations of motion, which were the basis of classical mechanics. In fact, these laws of motion were accepted as the ultimate theory of natural phenomena. But, alas, a new physical reality viz-electromagnetic phenomena, which was discovered in less than a hundred years dethroned the supremacy of the Newtonian laws and exposed their limitations, and also established that none of their features had absolute validity.
