Kural - 256

'We eat the slain,' you say, by us no living creatures die;
Who'd kill and sell, I pray, if none came there the flesh to buy

Explanation
If the world does not destroy life for the purpose of eating, then no one would sell flesh for the sake of money.

Tamil Transliteration
Thinarporuttaal Kollaadhu Ulakenin Yaarum
Vilaipporuttaal Oondraruvaa Ril.