Even the Wise Cannot See All Ends

What a pity Bilbo did not stab the vile creature, when he had a chance!

Pity? It was Pity that stayed his hand. Pity, and Mercy: not to strike without need.

I do not feel any pity for Gollum. He deserves death.

Deserves death! I daresay he does. Many that live deserve death. And some die that deserve life. Can you give that to them? Then be not too eager to deal out death in the name of justice, fearing for your own safety. Even the wise cannot see all ends.

– J. R. R. Tolkien, The Two Towers