One of the six famous heretical teachers of the Buddha's day. He was a great skeptic, his teaching being the evasion of problems and the suspension of judgment. His doctrines seem to have been identical with those of the Amarāvikkhepikas (Eel wrigglers) who, when asked a question, would equivocate and wriggle like an eel. Sañjaya's teachings are given at D.i.58; cf. the "Eel wrigglers" at D.i.27.
It is probable that Sañjaya suspended his judgments only with regard to those questions the answers to which must always remain a matter of speculation. It may be that he wished to impress on his followers the fact that the final answer to these questions lay beyond the domain of speculation, and that he wished to divert their attention from fruitless enquiry and direct it towards the preservation of mental equanimity.
Buddhaghosa gives us no particulars about Sañjaya, beyond the fact that he was the son of Belattha (DA.i.144). Sanskrit texts call him Sañjayī Vairatiputra (E.g., Mtu.iii.59f) and Sañjayi Vairattīputra (E.g., Dvy. 143,145).
He is evidently identical with Sañjaya the Paribbājaka who was the original teacher of Sāriputta and Moggallāna (Vin.i.39). It is said that when these two disciples left Sañjaya to become pupils of the Buddha, they were joined by two hundred and fifty others. Sañjaya then fainted, and hot blood issued from his mouth. Vin.i.42; according to DhA.i.78, Sāriputta and Moggallāna tried to persuade Sañjaya to accept the Buddha's doctrine, but they failed, and only one half of his disciples joined them. The Paribbājaka Suppiya was also a follower of Sañjaya (DA.i.35).
Barua thinks (Op. cit., 326) that the Aviruddhakas mentioned in the Anguttara (A.iii.276) were also followers of Sañjaya - that they were called Amarāvikkhepakā for their philosophical doctrines, and Aviruddhakā for their moral conduct.