This is why I am always more interested in what people will refuse to do than in what they claim to have the freedom to do. It's not that I'm a negative person, and by no means am I a rulemonger. But it is your No that gives value to your Yes. It sets a boundary. It indicates the point beyond which you cannot be pushed or inveigled. It sets your price.
Old sexist joke: A rotter asks a girl if she would go to bed with him if he paid her a million dollars. After thinking for a moment, the girl says yes. The rotter then asks if she would go to bed with him for ten bucks. Indignant, she says, "What kind of a girl do you think I am?" "We've already established that," says the rotter. "Now, we're just haggling over the price."
People who have a point beyond which they will not go, even if they suffer for it, have my respect -- even if I don't agree with their principles. They are at least solid, not gas. So, whether the question is one of money, or sex, or politics, or religion, or keeping promises -- wherever people are sitting around wondering what they should do, could do, might do, need to do, want to do, the first thing that must be done in the negotiations is to establish the point beyond which somebody in the discussion will not go. And until you reach that point, everybody is just laying down sales patter.
It follows from this that I want there to be as few definite Noes in my moral framework as possible, for comity's sake if nothing else. I want to give others as much freedom as I claim for myself, after all. I do not want to be a difficult person. And I want to live a quiet life. But when we finally reach a NO, then there's no more negotiation possible. My objection wasn't a negotiating ploy; there is no fallback position that I'll really settle for. I'd like you to respect my No, if and when we get there; but even if you don't, I must respect myself, and the answer isn't going to change, no matter what you offer or threaten.