In one sense there is no single universal valueThis destroys everything you say afterwards.
Ah, too bad you didn't continue reading. You know, that next sentence which began, "And yet..." ;-)
You're trying to derive value from fact in a purely deductive system. You want to start with an "objective" universal premise, and by deduction & deduction alone, generate moral judgements. The problem is, in the real world you can't deduce your way thru life. You need induction too. The justification of our ultimate values comes as much from our real-world lives as it does from any axioms we accept.
Plenty of people are suicidal; you have no reason that they shouldn't commit suicide if they want to. If all of society wants to commit suicide (or destroy itself), likewise. The problem is that you're reading a certain universal value into life that you've just admitted you can't justify - it might be of value to one beholder, but that of course doesn't make it objectively so.
If all society wanted to commit suicide, then the world would become a dangerous place indeed. But societies don't decide to destroy themselves, do they? People (except for the truly suicidal or deranged) want to live - it's the basic condition of any species; otherwise all would have gone extinct long ago. The worst that whole societies can do is pursue tragically foolish philosophies or moralities in pursuit of what are almost always quite reasonable basic goals. This is why I said:
And yet the difference between a life-affirming principle and a life-destroying principle is the difference between thriving and extinction. So my goal of a society that sustains the lives of humans as humans (as opposed to savages or slaves) is hardly something that needs to be justified. It's axiomatic, IMO. How could you begin to convince people that the goal they should be orienting their life around should be death & destruction?
As for how relative values can produce a moral code approaching objective validity, remember that morality by its very nature concerns principles of behavior.
Read it all... I just found it (to be irrelevant to proving/unable to prove) your point. I see little reason to reproduce non-vital parts of a discussion in my replies when Free Republic makes it easy to trace back to the post being replied to, not to mention it makes it a less convoluted read for everyone involved.
You're trying to derive value from fact in a purely deductive system.
In the line of argument I've been using, perhaps I have. But that is not to say that induction cannot be used to prove my argument - only that I have not yet used it. I try to stear clear of using inductive anecdotes because I'm convinced they're largely useless, or far less effective (and could end up diverting attention from the real points), when discussing theism as the only justification for objective morality. My reason for arguing this case is not necessarilly to prove theism true, or objective morality true, only to show the dependency of the latter on the former.
If all society wanted to commit suicide, then the world would become a dangerous place indeed. But societies don't decide to destroy themselves, do they? People (except for the truly suicidal or deranged) want to live - it's the basic condition of any species; otherwise all would have gone extinct long ago. The worst that whole societies can do is pursue tragically foolish philosophies or moralities in pursuit of what are almost always quite reasonable basic goals.
Here you again invoke ideas - "danger," "destroy," deranged," "worst," "tragic," etc. - that require universal value to be placed on humanity, or at least some aspects of it, in order to even be understood in your own argument. "Deranged," for instance, by its nature as a description insists that principles of human behavior are recognized in order that we also recognize aberrations from them - but those principles of behavior alone don't explain why it is bad to act deranged, only that it is relatively different to act deranged. In fact, "deranged" ends up losing its negative connotation and its reason for existing altogether as an idea seperate from "different."
Your entire line of thought seems to be:
1.) By and large (people/living things/whatever) don't seek the destruction of their own lives,
2.) Therefore, the (continuation/improvement) of (life/existence/whatever) is objectively good.
In other words, 'it is the regular occurence, thus we can infer that it is the good.' Is that really what you're saying?