The Vaisheshika system is one of the six Hindu schools of philosophy from ancient India. Vaisheshika is derived from the Sanskrit, vishesa, meaning “distinction” or “distinguishing feature.” The Vaisheshika system emphasis on metaphysics and naturalism. Acharya Kanada in around 6th to 2nd Century BCE presented his theory on Gravity in Vaisheshika-Sutra.
Acharya Kanada is also known as Kashyap. The concept of Atoms was also formulated by Acharya Kanada in Vaisheshika-Sutra.
Vaisheshika Sutra discusses the role of Gravity in mainly three events:
1) Why does an object fall on the ground when you let go?
To describe this first of all Sutra 5.1.6 states:
आत्मकर्म हस्तसंयोगाश्च ।
Action of body and it’s members is also from conjunction with the hand.
As the above Sutra describes that it is due to conjunction with hand object remains. Then the next Sutra describes that in the absence of conjunction, objects fall results due to Gravity.
संयोगभावे गुरुत्वात्पतनम (V.S. 5.1.7)
In the absence of conjunction falling results from Gravity.
Thus it clearly recognizes objects fall downward due to Gravity.
2) Why does an object fall after sometime when you throw in the air?
Then Vaisheshika sutra discusses the role of Gravity in falling of moving objects. It gives through the analogy of arrow. First, it gives mechanism of arrow projection in Sutra 5.1.17
नोदनाद्यभिषोः कर्म तत्कर्मकारिताच्च संस्कारादुत्तरं तथोत्तरमुत्तरं च ।।
The first action of arrow is from impulse; the next is resultant energy produced by the first action, and similarly the next next.
Then it explains why it falls in next Sutra.
संस्काराभावे गुरुत्वात्पतनम (V.S. 5.1.18)
In the absence of resultant/propulsive energy generated by action, falling results from Gravity.
3) Why do rainfall and evaporation occur?
Then the Sutras discuss the cause of falling of water from the sky.
अपां संयोगाभावे गुरुत्वात्पतनम (V.S. 5.2.3)
The falling of water in absence of conjunction is due to Gravity.
Then it discusses the flow of water.
द्रवथ्वास्यन्दनम् (V.S. 5.2.4)
Flowing results from fludity.
Then it discusses why water rises.
नाड्यो वायुसंयोगादारोहणम् ।(V.S. 5.2.5)
The Suns rays (cause) the ascent of water through conjunction with air.
Thus from above Sutras, we can acknowledge that Vaisheshika sutra clearly mentions about the Gravity. It uses the word “Gurutwa” which is also used in present time to represent Gravity. Gurutwa means force which arises due to mass.
Vaisheshika Sutras with translation here.