Kural - 214

Who knows what's human life's befitting grace,
He lives; the rest 'mongst dead men have their place

Explanation
He truly lives who knows (and discharges) the proper duties (of benevolence) He who knows them not will be reckoned among the dead.

Tamil Transliteration
Oththa Tharavon Uyirvaazhvaan Matraiyaan
Seththaarul Vaikkap Patum.