Reading Russ Shafer-Landau's book Moral Realism, I am struck by an irony. Moral realism says that our moral judgments make claims about the world that are sometimes true, and true in the nature of things, not true (as "constructivists" say) because of the way we reason, or the way we agree to live together under a social contract, or some such. A contrasting position (among many others) is non-cognitivism. On that view, a moral judgment is a disguised reaction--"Hurray for universal health care!" or "Boo, genocide!" The Big Problem for moral realists--as the book makes clear for many chapters--is explaining how moral judgments can be motivating, if they're beliefs about the world. Beliefs (all by themselves) aren't the paradigm case of a motivating state. The advantage of non-cognitivism, by contrast, is that it makes it easier to explain moral motivation. "Boo!" and "Hurray!" reactions are just the kind of thing that spur people to action.
But here's the irony. It's puzzling how moral beliefs motivate, but the acceptance of moral realism is motivating. Imagine being sent to a reeducation camp where it's beat into you by non-cognitivists that your moral judgments are just reactions. When you are released, I think you're going to have a hard time latching onto any cause that takes any energy. But gradually you'll probably go back to how we normally think about morality. As you return to thinking it's true that you should do something about global warming, you'll get fired up to actually do something.
It's interesting to ponder the "phenomenology of obligation." What does it feel like to believe that we (really, truly, objectively) ought to stop global warming? It feels like someone's telling you to do something. You're under order. Most of us don't think of our moral responses as mere reactions, but if we did, what would that be like? We'd back off and demur. "I think there should be universal health care, but that's just me."
Could it be that an implicit commitment to moral realism gives our beliefs about right and wrong some of the oomph that they have? Well, I'm pondering it. Frankly, I think I'd have to study these issues for the 10,000 hours required for expertise--if Malcolm Gladwell is right about that--before I really thought I had the right to an opinion, but we're all entitled to our erstwhile hunches and hypotheses.