author or one of the authors of two great Hindu classics: the first, Yoga-sūtras, a categorization of Yogic thought arranged in four volumes with the titles “Psychic Power,” “Practice of Yoga,” “Samādhi” (transcendental state induced by trance), and “Kaivalya” (liberation); and the second, the Mahābhāṣya (“Great Commentary”), which is both a defense of the grammarian Pāṇini against his chief critic and detractor Kātyāyana and a refutation of some of Pāṇini's aphorisms.

The Yoga-sūtras seems to span several centuries, the first three volumes apparently written in the 2nd century BC and the last book in the 5th century AD. Authorities therefore tend to credit more than one author writing under this name, although there is wide variance in opinion. There is a possibility that many men used this name, as it was used by the authors of a number of other works on such diverse subjects as medicine, metrics, music, and alchemy. The name itself is obviously a pseudonym, since it denotes no caste and implies divine descent from the Great Serpent, Śeṣa.