Agattiyam(Tamil: அகத்தியம்), according to mentions in Sangam Literature, was the first known book on Tamil grammar. This was supposedly written by the sage Agathiyar, and believed to be lost beyond redemption. The sage Agathiyar, according to Hindu legends, brought the Tamil language and its syntax to the Tamil people from the god Siva. Tolkappiyar (epithet), the author of Tolkappiyam, which is believed to be the oldest extant Tamil grammar, is held to be a disciple of Agathiyar.