Kural - 32

No greater gain than virtue aught can cause;
No greater loss than life oblivious of her laws

Explanation
There can be no greater source of good than (the practice of) virtue; there can be no greater source of evil than the forgetfulness of it.

Tamil Transliteration
Araththinooungu Aakkamum Illai Adhanai
Maraththalin Oongillai Ketu.