Kural - 1075

Fear is the base man's virtue; if that fail,
Intense desire some little may avail

Explanation
(The principle of) behaviour in the mean is chiefly fear; if not, hope of gain, to some extent.

Tamil Transliteration
Achchame Keezhkaladhu Aasaaram Echcham
Avaavuntel Untaam Siridhu.