சிவனிடத்திலும், முருகக் கடவுளிடத்திலும், தமிழைக் கேட்டுணர்ந்து, அத்தமிழில் அகத்தியமென்னும் இலக்கண நூலையும், அரிய, பெரிய, வைத்திய, வாத, யோக, ஞான நுாற்களையும் எழுதிய வோர் முதன்மையான சித்தர் இப்பொழுது இவர் பேரால் வழங்கும் நுாற்கள் போலிநுாற்களே. இவர் எக்காலத்தவர் என விளங்கவில்லை. இவர் இப்பொழுதும் பொதிகை மலையில் வசித்திருப்பதாகக் கருதப்படுவர். இவர் பதினொன் சித்தர்களில் ஒருவர் - He is an enlightened Personage amongst the Siddhars. He received tuition from the God Siva and Murugar in Tamil and is said to have written more than 50 treatises on Medicine, Alchemy and Magic, Composed at different periods. He compiled the first Tamil Grammar (Agathiyam). Besides the many valuable works mentioned, above, he has also written various dissertations on Moral and Natural Philosophy and only some of them are now in existence. His thirty (முப்பது) stanzas are like the wisdom of Solomon. It is difficult to ascertain the period, at which he lived, although Dr. Caldwell fixes it as the 6th or 7th century, B.C. He is one of the greatest writers of antiquity amongst the Tamilians and is said to have had a Divine origin. The popular belief is that even now, at times, he is visible and that his healing spirit hovers amongst the mountains of Courtallum in Tinnevelly District. Some of the works now in existence in his name are said to be not his productions at all but literary forgeries. He is one of the 18 forming the Siddhar's school.