Jaimini was an ancient rishi (sage), who was a great philosopher of the Mimansa school of Indian philosophy. He was the disciple of the great Rishi Veda Vyasa, the son of Rishi Parashara

Parashara

' is a Rigvedic Maharishi and author of many ancient Indian texts. Parāśara was the grandson of Vashista, the son of Śakti Maharṣi, and the father of Vyasa. There are several texts which give reference to Parāśara as an author/speaker...

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Jaimini is most known for his great treatise Purva Mimamsa Sutras

Purva Mimamsa Sutras

The Mimamsa Sutra or the Purva Mimamsa Sutras , written by Rishi Jaimini is one of the most important ancient Hindu philosophical texts. It forms the basis of Mimamsa, the earliest of the six orthodox schools of Indian philosophy...

 (“First Reflection”), or Karma-mimamsa (“Study of [Ritual] Action”), a system that investigates the nature of Vedic injunctions. The text founded the Purva-Mimamsa school of Ancient Indian philosophy, one of the six Darsanas or schools of Ancient Indian philosophy.

Dated to ca.