Hello philosophers in a recent debate I was involved in a theist stated “For morality to be objective, moral propositions such as "Killing is bad","Stealing is bad", etc... need to be true independently of the person who is stating them. “ I countered “That is the way this position is normally put but a problem arises as in if there are objective moral facts how would we know this to be the fact? To know something is an objective moral fact only needs an agent to know this , how can a moral fact be known independent of a human mind to decide?” Is my position logically sound or are there problems with my reply?

I think your counterargument is conflating issues that need to be kept distinct.

Your interlocutor ((I'll call him or her your friend) said, correctly, that if morality is objective, the truth of moral claims doesn't depend on the person who makes them. That seems fine. To say that something is objectively true is to say that it's true whether or not anyone believes it.

Your response was to ask how we could know that there are objective moral facts, if there really are. But that's a separate issue, and in fact it has nothing in particular to do with moral claims. If there are objective facts about what's going on now (say, in the Earth's frame of reference) in some remote part of the universe, then those facts are facts whether or not we could ever be in a position to know them. Whether X is mind-independently true and whether anyone is in a position to know that X is true are different matters.

You ask: "how can a moral fact be known independent of a human mind to decide?" That's ambiguous. Obviously nothing can be known independently of minds, human or otherwise, because knowledge is a case of belief, and beliefs are mental states. But once again: whether something is true and whether it's known or even believed are different matters.

But your wording hints at something else. It suggests that as you see it, moral claims are special: they aren't the sort of thing that could be true at all independent of someone deciding that they are true or accepting them or committing to them.

If that's what you mean, then you and your friend don't necessarily disagree. You quote your friend as saying that if morality is objective, moral truths don't need to be believed to be true. However, that's a conditional claim. It's compatible with moral claims not actually being objectively true at all. It just reminds us of what we mean when we say that something is objectively true.

So I'm guessing that the real disagreement is over the question of whether moral claims could be objectively true, I'm guessing that your friend thinks the answer is yes, and you think it's no. Both of you are in good company. There are interesting defenses of both point of view.

Now there's a further idea that may or may not be in the background. It holds that truth can't float free of the possibility of knowing the truth. On this view, the idea that there might be some truth that no one could even possibly know is a confusion. Perhaps that's correct, though I'm not inclined to think so myself. But notice that it has nothing in particular to do with morality. Rather, it amounts to saying that a certain notion of objectivity is misplaced from the outset. I suspect that's not what you're saying. If I'm right, then what you would need to do to advance the argument is to say what in particular it is about morality that gets in the way of it's being objective in the sense that your friend has pointed out.

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