James Lenman, Morality without metaphysics, at "OUPblog":
This is the everyday world of moral common sense but there are always sceptical voices: perhaps it’s just nonsense. Can there really be truths, proper objective truths about what is and isn’t okay just the way there are objective truths about chemistry and geology? Some people argue that it makes no sense to suppose there are moral truths somehow baked into the constitution of the universe, radically independent of human beings and our moral experience, and so morality is nonsense.
I argue that while that rather grandiose metaphysical picture is indeed false, the best way of understanding our moral common sense presupposes nothing so fancy nor so fanciful. There need only be human beings jointly committed to a shared enterprise of living together in peaceful and orderly moral community regulated by norms of justice and civility that we can justify to each other in a shared currency of reasons shaped by and expressive of our passionate natures. It is not so complicated. For many good reasons, I don’t want to live in a world where we say it is okay to beat someone to death because you do not like the way they dress. Neither do you. So let’s not.
Oh, is that all it takes? We don't need moral truths baked into the constution of the universe independent of us; instead, all we need baked into the universe independent of us is:
the conditions for the existence of human beings capable of justifying norms by reasons shaped by passions;
the conditions for the possibility of joint commitments to shared enterprises of living together;
the conditions for the possibility of peaceful and orderly moral community;
the conditions for the possibility of norms of justice and civility that are capable of being justified by reasons;
and the conditions for the ability of norms to regulate communities in some way.
I have to say, though, that that is starting to look an awful lot like "moral truths somehow baked into the constitution of the universe, radically independent of human beings and our moral experience." Whatever way you run things, either this is a universe structured so that moral and immoral behavior is really possible, or it is not. Carl Sagan famously said that if you wish to make an apple pie from scratch, you must first invent the universe. Likewise, if you want to have a morality, you first must have the metaphysics for it. You need "baked into the constitution of the universe" moral agents capable of moral thinking about the possibility of moral community in light of moral norms in a way that can be rationally evaluated. A universe that allows these things is a universe that has at least some moral truths 'baked in', even if for some reason you want to insist that they are very general. And, of course, moral common sense tells us that we do in fact experience the universe to have these things, so your account of the universe had better allow it to do so -- not that the universe had to wait for your permission, of course.
The weird thing is that this is literally what Lenman goes on to say, in different words, since he thinks he's determined by the universe to value morality, and apparently all or most of the human race, too; apparently determined purely contingently, which gets a little confusing. But regardless, it's a universe that makes morality possible and in our case actual; and that's a metaphysical point worthy of some reflection.