What details do our scriptures mention about Maharshi Kanad and (his theory) on Paramanus or atoms?
The Vaiśeṣika is one of the six classical schools of Indian philosophy. It is known for its naturalism and was founded by Sage Kanada Kashyap. The Encyclopedia Britannica cites 2nd-3rd century CE as the possible time-period of its founding. However, Dr. Subhash Kak has placed the formation of the Vaiśeṣika system to 600 BCE.
Within this fascinating Darśana, an atomic theory is proposed. According to the description in Encyclopedia Brittanica (on-line edition, updated 5/2015):
The Vaiśeṣika system holds that the smallest, indivisible, indestructible part of the world is an atom (anu). All physical things are a combination of the atoms of earth, water, fire, and air. Inactive and motionless in themselves, the atoms are put into motion by God’s will, through the unseen forces of moral merit and demerit.
According to April Holloway (Editor of the "Ancient Origins" website), Acharya Kanad formulated this atomic theory 2,500 years before John Dalton proposed the modern reiteration of atomic theory in chemistry and physics. According to the eminent Australian Indologist, A.L. Basham, the ideas of Rishi Kanad Kashyap were "brilliant imaginative explanations of the physical structure of the world, and in a large measure, agreed with the discoveries of modern physics."
Amita Chatterjee, Professor of Philosophy & Coordinator of the Centre for Cognitive Science, has written about the Vaiśeṣika system in the Oxford Handbook of World Philosophy. Along with Nyāya, Vaiśeṣika is described as follows:
"...committed to common-sense realism and pluralism in their ontology; believe in the creation of the world from material atoms that conjoin to generate this world by the will of God and in accordance with the accumulated merits and demerits of individual agents; accept a theory of causation according to which a new effect is produced by its cause and is not a mere manifestation of the cause; and admit that liberation means absolute cessation of suffering, a state where the liberated self is without any consciousness."
Note how the description of liberation within the Nyāya-Vaiśeṣika dyad differs from the other Darśanas (like Yoga and Vedānta).
According to the Vaiśeṣika Sutras, there are 9 categories of reality: 1) Four classes of atoms (earth, water, light, air); 2) Ākāśa [ Sanskrit: आकाश ] = space or aether; 3) Kāla = time; 4) Dik = direction; 5) Ātman = soul (i.e., an infinite number of souls); 6) Manas = mind.
According to the Indian-American scientist, Dr. Subhash Kak:
"In my own study of the Vaiśeṣika, I have become convinced that Kaṇāda is perhaps the greatest physicist before Newton.... he anticipated most of Newton’s laws of motion. Further, he attempted something that no physicist to date has dared to do: he created a formal system that includes space, time, matter, as well as observers." [Passage is from "The Greatest Unsung Indian", published in Swarajya]
Maharshi Kanad ( महर्षी कणाद) was born in 600 BC in Prabhas Kshetra (प्रभास क्षेत्र) near Dwaraka (द्वारका) in Gujarat, India. He is also known as Kashyap Rushi (कश्यप ऋषी) Once Kashyap Rushi was on a pilgrimage to Prayag when he saw thousands of pilgrims lettering Rice grains and flowers in the streets which they offered at the temple. Rishi Kashyap, began collecting the grains of that rice. People gathered around him to see why he is collecting grains from the street. People asked kashapa why he is doing so ? He said that each single grain in itself may seem worthless, but a collection of hundred grains make up a person's meal, the collection many meals would feed an entire family and ultimately the entire mankind was made of many families, thus even a single grain of rice was as important as all the valuable riches in this world.
Since then, people started calling him ‘Kanad’, (कणाद) as ‘Kan’ (कण) in Sanskrit. ‘the smallest particle’. Kanad carried out study about this unknown world of small particles and stated his theories about Kana (atom) (अणू).
For this discovery people gave him the title Maharshi Kanad (महर्षी कणाद).
In his work Vaisheshika (वैषेशीका) sutras. He has described the smallest particle (Kana or Atom) (कण , अणू). The Scriptures are from Vaisheshika sutras by him.
1) अणूसंयोगस्तवप्रतिषिद्ध: - 4.2.4
Meaning- Anusanyog (अणूसंयोग )=Conjunction of atoms Tu (तू) = But , Apratisiddhah (अप्रतिषिद्ध:)= Not denied.
2) अतोविपरितमणु - 7.1.10
Meaning - Atah (अत:) = Of this Viparith (विपरितः)=Contrary Anu(अणू)= The minima of magnitude
The contrary of this is Anu.
3) अग्नेरूर्ध्वज्वलनं वायोस्तीर्यक्वपवनमणूनां मनसश्र्चशदयं कर्मादृष्ढकरितम ।। 5.2.13
Meaning- Agne (अग्ने)= Of fire. Urdhwajwalanam (ऊर्ध्व ज्वलनं) = Flaming Upward
Vayoh (वायो:)= Of air
(Pawanam) पवनं = Of wind Anunam
(अणुनां) = Of fundamental particles.
Mansah (मनस:) = Of Mind
Ch (च)= And
Adyam (आद्यमं)= Initial, first
Karma drusha karitam(कर्मादृष्ढकरितम) = action caused by adristam or invisible.
The initial upward flaming of fire, the initial sideward blowing of air and the initial action (motion) of anu, and of mind are caused by adristam or Invisible.
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