Kanada, also known as Kashyapa, Ulūka, Kananda and Kanabhuk, was an ancient Indian natural scientist and philosopher who founded the Vaisheshika school of Indian philosophy that also represents the earliest Indian physics.

Kanada
Philosopher
Kanada, also known as Kashyapa, Ulūka, Kananda and Kanabhuk, was an ancient Indian natural scientist and philosopher who founded the Vaisheshika school of Indian philosophy that also represents the earliest Indian physics.
Born: Gujarat

Kanada (Sanskrit: कणाद, was an ancient Indian natural scientist and philosopher who founded the Vaisheshika school of Indian philosophy that also represents the earliest Indian physics.
Estimated to have lived sometime between 6th century to 2nd century BCE, little is known about his life. His traditional name “Kanada” means “atom eater”, and he is known for developing the foundations of an atomistic approach to physics and philosophy in the Sanskrit text Vaiśeṣika Sūtra. His text is also known as Kanada Sutras, or Aphorisms of Kanada.
The school founded by Kanada explains the creation and existence of the universe by proposing an atomistic theory, applying logic and realism, and is one of the earliest known systematic realist ontology in human history. Kanada suggested that everything can be subdivided, but this subdivision cannot go on forever, and there must be smallest entities (parmanu) that cannot be divided, that are eternal, that aggregate in different ways to yield complex substances and bodies with unique identity, a process that involves heat, and this is the basis for all material existence He used these ideas with the concept of Atman (soul, Self) to develop a non-theistic means to moksha. If viewed from the prism of physics, his ideas imply a clear role for the observer as independent of the system being studied. Kanada’s ideas were influential on other schools of Hinduism, and over its history became closely associated with the Nyaya school of Hindu philosophy.
Kanada’s system speaks of six properties (padārthas) that are nameable and knowable. He claims that these are sufficient to describe everything in the universe, including observers. These six categories are dravya (substance), guna (quality), karmana (motion), samaya (time), visesa (particular), and samavaya (inherence). There are nine classes of substances (dravya), some of which are atomic, some non-atomic, and others that are all-pervasive.

The ideas of Kanada span a wide range of fields, and they influenced not only philosophy, but possibly scholars in other fields such as Charaka who wrote a medical text that has survived as Charaka Samhita.
Kanada presents his work within a larger moral framework by defining Dharma as that which brings about material progress and highest good.] He follows this Sutra with another that asserts that the Vedas have gained respect because they teach such Dharma, and something is not Dharma simply because it is in the Vedas.
Kanada makes empirical observations such as the rising upwards of fire, magnetic movement, rain and thunder, the growth of grass, and offers naturalistic explanations to them in his text Vaisheshika Sutra.
Kanada and early Vaisheshika scholars focused on the evolution of the universe by law. However, this was not unusual for his times since several major early versions of Hindu philosophies such as Samkhya, Nyaya, Mimamsa along with sub-schools of Yoga and Vedanta, as well as non-Vedic schools such as Jainism and Buddhism, were similarly non-theistic. Kanada was among the sages of India who believed in man’s potential to understand existence and reach moksha on his own, without God, a notion of ancient Indians summarised by Nietzsche as the belief that “with piety and knowledge of the Veda, nothing is impossible”.
The text states:
There are nine constituents of realities: four classes of atoms (earth, water, light and air), space (akasha), time (kāla), direction (disha), infinity of souls (Atman), mind (manas).
Every object of creation is made of atoms (paramāṇu) which in turn connect with each other to form molecules (aṇu). Atoms are eternal, and their combinations constitute the empirical material world.
Individual souls are eternal and pervade material bodies for a time.
There are six categories (padārtha) of experience — substance, quality, activity, generality, particularity, and inherence.
Several traits of substances (dravya) are given as colour, taste, smell, touch, number, size, the separate, coupling and uncoupling, priority and posterity, comprehension, pleasure and pain, attraction and revulsion, and wishes.
Thus the idea of the subdivision is carried further to analytical categories as well, which explains its affinity with Nyaya.
Apart from this Kaṇāda might have already presented the same laws of motion attributed to Newton, as part of the Vaiśeṣika Sutras.
वेगः निमित्तविशेषात कर्मणो जायते। वेगः निमित्तापेक्षात कर्मणो जायते नियतदिक क्रियाप्रबन्धहेतु। वेगः संयोगविशेषविरोधी॥
Meaning, action on objects generates motion. The external action being direction causes the motion to be directional. An equal and opposite action can neutralise the motion.
In the fifth chapter of Vaisheshika Sutra, Kanada mentions various empirical observations and natural phenomena such as the falling of objects to the ground, rising of fire and heat upwards, the growth of grass upwards, the nature of rainfall and thunderstorms, the flow of liquids, the movement towards a magnet among many others, asks why these things happen, then attempts to integrate his observations with his theories on atoms, molecules, and their interaction. He classifies observed events into two: those caused by volition, and those caused by subject-object conjunctions.
His idea of the observer, that is the subject, being different from objective reality is completely consistent with Vedanta, which speaks of the difference between “Apara” and “Para” knowledge, where “Apara” represents normal associational knowledge whereas “Para” represents deeper subjective knowledge.
The concept of paramanu (atom)
Kanada proposes that paramanu (atom) is an indestructible particle of matter. The atom is indivisible because it is a state at which no measurement can be attributed. He used invariance arguments to determine properties of the atoms. 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 the same substance combined with each other to produce dvyanuka (diatomic molecules) and tryanuka (triatomic molecules). 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 postulated four different kinds of atoms: two with mass, and two without. Each substance is supposed to consist of all four kinds of atoms.
Kanada’s conception of the atom was likely independent from the similar concept among the ancient Greeks, because of the differences between the theories. For example, Kanada suggested that atoms as building blocks differ both qualitatively and quantitatively, while Greeks suggested that atoms differed only quantitatively but not qualitatively.