-[If].. morality exists (ie exists independent of the human mind)so moral propositions contain a truth value that expresses truth independent of a rational mind
Interesting Q: it does not follow that because moral propositions are not grounded in human minds that therefore they are not grounded in a rational mind. If you mean by "objective morality" the essential instantiations of the Good: No, humanity does not exist as a necessary condition for the Good. Similarly (one level down), as the Good exists in the world of say contingent being, humanity interacts as 'secondary cause' accidentally. Moving down completely to our nature (thus two higher) the truth of the Good as comprehended in the natural order does have epistemic conditions of say apprehension, but those wouldn't indicate that the truth value of 'moral propositions' are by necessary reduction our nature. So, when you ask about stealing apart from humanity there is either an incomplete scenario or a dangling predicate.

The Good does not reduce to the instance "humanity" finally, nor is it evaluated by us without any referent: for when you say 'no humans' this would by your scenario include us. You then ask a different question: "Would the proposition "stealing is wrong" be a coherent statement " it both does not follow that "there is no subject" nor that there is not a possible consideration. We can abstract the concept of "stealing" and recall the nature of a moral instance (not a material 'object') and then apply it a hypothetical, and answer your question: in possible instances of stealing: stealing is wrong. The question seems 'impossible' in the causal sense, but possible in that {and precisely because the Good is not an object(s)} we can begin with an understanding of what you mean, and that it invokes something morally reprehensible. It thus "implies": a subject, but does not reduce to him, an object (in this causal sense) but is not identical to it, and the world by secondary instantiation.

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ill write you a message when I make some django vids. thanks for the wonderful comment!

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