no reason for peace?

When you have an AI down to one worthless city, is there ever a reason to make peace? In my present game, Nebby backstab DOWed twice, so I took out his cap and another city. All there is left is a city only worthy of razing.

My question - should I ever accept peace? He'll just denounce me, and will never be a trading partner. No war weariness to worry about, so I can't see any choice but permanent cold war.

Thoughts?

If the world hates him and likes you, then being denounced by him would actually be a good thing diplomatically. (It would speed up the process of some other AI DOWing him and removing him from the game for you)

Terminology: "Cold War" is not staying in a state of war and doing nothing. Being in a state of war but doing nothing is called a "Phony war". But with you having been active early in it, this would be "war extended via diplomatic irregularity"
A "Cold War" is being in a state of peace; but fighting him thru other means (such as denouncing, attempting to embargo him / etc.)

I knew cold war was not the correct term, but it's late.

Standard size map. I have one friend, decent relations with the others. Too early (600AD) for much in relations. But rather than do the denounce dance, maybe I'll try to bribe a neighbor to take him out. His other neighbors are pretty weak, but a close CS could just about do the job right now.