Each of the above concepts has been discussed in the preceding chapter. Here, we shall briefly compare the Jain views about these concepts with those of modern science.
Having accepted the reality of physical substance, the Jain naturally accepts the reality of motion. It has also obtained a good standing in the field of modern philosophy and modern science has also emphasized the importance and reality.of motion in understanding the nature of physical existence. And, in order to accept the reality of motion of physical objects, the reality of space must also be accepted.
But motion in Jain doctrine is intimately connected with not only space, but also two other substances—positive ether (dharmāstikāya) as medium of motion and negative ether (adharmāstikāya) as medium of rest. We shall, therefore, be required to discuss all the three substances together with motion.
It may be recalled that we translated the terms dharmāstikāya and adharmāstikāya as positive and negative ethers respectively, because the classical physics had postulated the existence of medium of motion and called it ether. In the classical physics, the problem of motion was first dealt with by Gallillio and later on by Newton. Before them, Aristotlean tradition of absolute rest was generally believed. But Newton's theory got rid of the idea of absolute rest and introduced conception of a substance called the "ether", that was present everywhere, even in the empty space. Maxwell's electromagnetic theory of light predicted that light waves travel at a certain fixed speed through ether. Light waves travelled through ether as soundwaves travelled through air. Between 1887 and 1905, the fate of ether was hanging in a balance.In the meanwhile, an important experiment carefully performed by Michelson and Morely suggested that there exists no such substance as ether. Finally, in 1905, Albert Einstein established that the whole idea of an ether was unnecessary, provided that one was willing to abandon the idea of absolute time.
The discoveries of modern science, the dual nature of matter, the standing wave-patterns of electrons are all associated with the reality of space and its contents. Now the space itself, according to Jains, has infinite extension and only a portion of it is filled in the other real substances. It is this finite portion which is the theatre of all the drama of cosmic dance. And the finiteness of the cosmos is due to the two other substances viz. media of motion and rest. Without these two, the systematic structure of the cosmos would have been a chaos.