Dating ancient Tamil literature is however, a problem. Most scholars agree that the Tolkappiyam is the earliest extant Tamil grammar and literary work, as some of its archaic structures and considerations of style place it earlier than what has come to be called Sangam literature.
So it would be reasonable to accept its date as somewhere round the third century BC. But some scholars place it as late as fourth or fifth century AD. This work may be called the fountainhead of all literary conventions in Tamil literature. The influence of Sanskrit on it was peripheral. Tolkappiyar, who wrote it, is supposed to have been a disciple of Rishi Agastya, the purported author of the Agattiyam, a magnum opus and grammar of letters—which, however, is found only in small pieces quoted by medieval commentators.