I don’t want to live in a world where it’s “kind of ok” for a dad to kill his daughter because she wants a divorce. But that’s the world you’ve created.
Who on earth said it was ‘kind of OK’ to kill a daughter for getting a divorce? It is in no way OK at all. Perhaps you seem to think that if the father can come up with some reasons for killing her, then that grants it some validity. Is that what you are saying? That because it is wrong there can never be a reason he can give for doing it? Which is, if that is indeed what you are implying, bizarre.
The problem you keep side-stepping is when someone uses* the very same model which you are using.*…but comes up with a different idea of what’s moral.
You, with your denial of objective morality, can only say: well, that’s right for you, I guess, to kill your daughter. You used your reason, logic, risk/benefit ratio, and came up with your own answer.
Leave out the ‘only’ and what on earth is wrong with that? The fact that we both disagree with him does not, in any way whatsoever, stop him from having reasons. It is, undoubtedly and without any question whatsoever, the right thing for him to do. Fathers don’t kill children for no reason at all. How you can deny this is beyond me. The fact that he is wrong has no bearing on the fact that he thinks he is right. People who fly planes into buildings do so because they believe they are right. People who commit genocide do so because they think they are right. In neither case is it ‘kind of OK’ simply because they have reasons for doing it.
Now…IF OBJECTIVE MORALITY EXISTS, then you can tell him: you are wrong.
If you have to resort to that, literally admitting that your arguments are not good enough then, as I said before, your arguments have obviously failed.
But if there is no such thing as objective morality, all you can say is, just like you would say to someone who likes mashed turnips, “Different strokes I guess!”
(Imagine how ridiculous it would be to tell someone: you are wrong for liking mashed turnips!.
Not so ridiculous: you are wrong for killing your daughter.
What’s the difference? With the former, there is no right or wrong answer. With the latter, there is a right answer and a wrong answer.)
If you just yell out Objective Morality! and leave it at that, you are saying that no reasons need be given. But surely, even if something is Objectively Wrong, it must be so for some reasons. So articulate them. Tell me why, without mentioning God, Natural Law, the church or anything at all to do with religion, why he should not kill his daughter. Give me your reasons.
If you can do it, there’s no need to mention objectivity at all (it will be wrong for the reasons given - no need to play any trump cards). If you can’t do it, if you can’t give good reasons, then you lose the argument.