Conversations with Angie: The meaning of "objective moral values"
With these distinctions in mind, I think I can answer your question. This is what you said:
I guess it comes down to the claim that good and evil have to be objective. Maybe they do NOT have to be objective. Can't it just be true that humans created the moral systems as their societies developed, and that they are still legitimate and valid? Most people groups have created codes forbidding stealing and violence, etc., and specifying punishments for transgressors. Fundamentally, the codes are the same for most of the world's people groups (as far as which behaviors are acceptable and which ones are not - the punishments obviously vary more).
Yes, I would agree that different people and cultures can come up with rules they all agree on. They would be true in the sense of being real descriptions of that culture's values. But they wouldn't be true in the objective sense, because you might have another culture who has a different point of view. If morality depends on culture, then that's cultural relativism. One culture, for example, may condone slavery while another condemns it. So is slavery right or wrong? Well there's no objective truth to the matter. It's just a matter of whether a culture agrees with it or not. When a person in some culture says, "Slavery is wrong," they aren't really describing slavery if morality is only a matter of cultural convention. Rather, they're describing their culture's socially constructed view of reality. They're describing the subjective preferences and values of their culture. They're describing how their culture feels about slavery. But slavery itself is neither right nor wrong on that view.
If slavery itself were wrong in the objective sense, then it would be wrong whether any culture agreed with it or not. Just as the earth would be round even if we thought it was flat, so also would slavery be wrong even if we thought it was right, assuming slavery is wrong in the objective sense.
I hope it's clear now what I mean by "objective moral values." Whether any moral values ARE objectively true is what the second premise in the moral argument is about, so I'll talk about that another time. Right now I just want to stick to the first premise.
to be continued...
Conversations with Angie: If there is no God, then there are no objective moral values