Vatsyayana(4th c.) was a writer and commentator in the Nyaya school of ancient Hindu philosophy.
The Nyaya school has been integrated with another of the six schools, the Vaisheshikas, from the early common period.
Vatsyayana is most known for his commentary on Gautama's
Nyaya Sutras, which are the Nyaya school's fundamental literature.
You may also want to read more about Hinduism here.
Be sure to check out my writings on religion here.