Maharshi Kanada was ancient Indian scientist, sage and philosopher who founded the philosophical school of Vaisesika and authored the text Vaisesika Sutras or Aphorisms. He pioneered atomic theory, described dimension, motion, chemical reactions of atoms.
Vaisesika Sutras are a blend of science, philosophy and religion. The essence of these Sutras is the atomic theory of matter.
It was Kanada who originated the idea that anu (atom) was an indestructible particle of matter. An interesting story states that this theory occurred to him while he was walking with food in his hand. As he nibbled at the food in his hand, throwing away the small particles, it occurred to him that he could not divide the food into further parts and thus the idea of a matter which cannot be divided further came into existence. He called that indivisible matter anu, i.e. atom. He also stated that anu can have two states – Absolute rest and a State of motion.
Adherents of the school of philosophy founded by Kanada, considered the atom to be indestructible, and hence eternal. They believed atoms to be minute objects invisible to the naked eye which come into being and vanish in an instant. Vaiseshikas further held that atoms of same substance combined with each other to produce dvyanuka (biatomic molecules) and tryanuka (triatomic molecules). This devinuka has the properties similar to those of the two original paramanu. Kanada also put forward the idea that atoms could be combined in various ways to produce chemical changes in presence of other factors such as heat. He gave blackening of earthen pot and ripening of fruit as examples of this phenomenon.
Kanada, the scientist identified different or a variety of Paramanus. He said that each paramanu has a specific property which is same as the class of substance to which it belongs to. This peculiar property has made to be called vaisesika sutra.
Paramanu or atom belonging to different classes of substance could also combine in large numbers., “because of the peculiarily or speciality of paramanu all things seen in the world are formed” he said.
His primary area of study was Rasavādam, considered to be a type of alchemy. He is said to have believed that all living beings are composed of five elements: water, fire, earth, air, ether. Vegetables have only water, insects have water and fire, birds have water, fire, earth and air, and Humans, the top of the creation, have ether—the sense of discrimination (time, space, mind) are one. He theorized that Gurutva (Hindi/Sanskrit for Gravity) was responsible for the falling of objects on the Earth.
Heat is the root cause for a change. When you heat a substance there will be a change. Due to heat mango ripens. Due to heat the earthen pot blackens. Due to heat water boils. So Kanada claimed that heat was responsible for any change.
This Indian conception of the atom was developed independently and possibly prior (depending on which dates one accepts for the life of Kanada) to the development of the idea in the Greco-Roman world. Indian theories about the atom are greatly abstract and enmeshed in philosophy as they were based on logic and not on personal experience or experimentation. Thus the Indian theories lacked an empirical base, but in the words of A.L. Basham, the veteran Australian Indologist “they were brilliant imaginative explanations of the physical structure of the world, and in a large measure, agreed with the discoveries of modern physics.”
According to author Dilip M. Salwi, “if Kanada’s sutras are analysed, one would find that his atomic theory was far more advanced than those forwarded later by the Greek philosophers, Leucippusand Democritus.”