Kural - 476

Who daring climbs, and would himself upraise
Beyond the branch's tip, with life the forfeit pays

Explanation
There will be an end to the life of him who, having climbed out to the end of a branch, ventures to go further.

Tamil Transliteration
Nunikkompar Erinaar Aqdhiran Thookkin
Uyirkkirudhi Aaki Vitum.