I was pulled into a facebook discussion today about moral realism. I decided I should use that as an excuse to write a short blog-post outlining some philosophical considerations which, I think, should lead us to affirm moral realism with confidence.
First, if there are properly basic beliefs which are not analytic, it seems that the belief in moral realism will definitely be properly basic. If we adopt a purely pragmatic account of epistemic justification then it also seems as though moral realism will be preferable to its negation. In fact, on a variety of epistemologies it looks as though moral realism fares pretty well. What kind of epistemology would justify moral anti-realism? I think the epistemologies which come to mind seem more philosophically suspicious than their competitors. So, unless we have a defeater for moral realism, we seem to be well within our rights to accept moral realism.
What might that defeater be? I suppose one could argue that if Naturalism is true, the moral anti-realism is true, but Naturalism is true, therefore et cetera. However, what reason do we have for believing that Naturalism is true? In all my time as a philosopher I have still yet to hear an even half-way decent argument for Naturalism. I would invite Naturalists to offer arguments here, but experience and my gut both tell me that most Naturalists have, at best, a vague sense that Naturalism seems right, and a poorly thought out set of reasons for thinking that metaphysical naturalism is true. Nevertheless, I remain open to incoming arguments, should anyone wish to present them. I should note, however, that even on Naturalism one should do whatever they can to make room for moral realism, for instance by trying to work out an account of Moral Naturalism.[1]
Second, there is a reductio ad absurdam we can run against arguments for moral anti-realism, which, if I recall correctly, W.L. Craig has presented. The idea goes like this: any argument you could give against moral realism can be parodied with near perfect parity into an argument against belief in the noumenal external world apprehended through the empirical senses. In the case of the external world we apprehend through the five senses that there is such a thing, which seems mind-independent and experience-independent. We have, of course, never verified that the external world is there absent any experience at all, and this is why we occasionally run into philosophers who adopt subjective idealism and deny that there is any such thing as a mind/experience-independent world. We are in a similar position with respect to our meta-ethical beliefs. In our moral experience we apprehend (through experience) that there are moral duties, values and facts which appear to be as objective as anything else we apprehend by experience. We naturally conclude that we encounter, in and through our moral experiences, a moral reality, a world of objective moral facts. In fact, our belief in moral realism is closer in kind to our belief in the noumenal external world than are our beliefs in mathematical facts or modal facts. The latter are the result of the operations of pure reason, whereas the former are the deliverances of experience.
There is, we think, something objectively real about the rock we touch, but this judgment is as much an intellectual knee-jerk reaction as it is possible to conceive. We have the same kind of intellectual knee-jerk reaction when it comes to moral realism, and the reaction comes with just as much force. It takes equally extreme cunning to convince ourselves to believe in moral nihilism as it does to fool ourselves into accepting subjective idealism. Both are just forms of skepticism. In fact, if one puts the arguments down on paper and compares them it will become obvious that there is no reason to deny moral realism which won’t count as an equally good reason to deny the noumenal external world. The subjective idealist won’t be impressed with this reductio, but most people will be.
Third, we can argue in the spirit and fashion of G.E. Moore, whose famous response to the skeptic was “I have a hand!” G.E. Moore’s point was that he would always be more sure that he had a hand than he could be that any argument for skepticism was sound. He might think that all the premises seem true, and agree that the argument seems logically valid, but he would deny that this gives him good enough reason to think that such an argument is sound. The credence which an apparently sound argument for skepticism provides would always, according to Moore, be outweighed by the credence given by experience for the proposition that he has a hand. No argument for skepticism, however good, will justify embracing skepticism, because no argument can make skepticism more plausible than things like ‘that I have a hand.’
To illustrate this point with an analogy, let’s use a logical argument for being skeptical of logical entailment. Suppose a teacher tells her elementary students that they will have a surprise quiz next week. Susie, a young student and budding logician, figures that the quiz wouldn’t be a surprise if it were on Friday, since they would have gone all week without it and would, therefore, be expecting it on Friday. She concludes that the surprise quiz can’t take place on Friday. However, she reasons that since Friday has been logically eliminated, the quiz cannot take place on Thursday either, since, if it hadn’t occurred until Thursday, but the quiz can’t possibly be a surprise Friday, then it can’t be a surprise Thursday either. She continues this process of elimination and determines that there is no day next week on which it is possible to have a surprise quiz. She has not made any obvious logical error in her reasoning, and yet just imagine her surprise when she has a quiz on Tuesday! Therefore, logical reasoning doesn’t always lead from true premises to true conclusions, even if it starts off with true premises and at each step the logical structure of the argument is impeccable.
What are we to make of such an argument? Well, we could come up with very clever responses, but Moore’s point is that even if we weren’t clever enough to discern where the reasoning is going wrong, we would (and should) still not accept that the argument justifies skepticism about logic! I am, and always will be, more sure of modus ponens than I can be that an argument for logical contradiction is sound. This is Moore’s point, and it translates well to the issue of moral realism/anti-realism.
The Atheist philosophy Louise Antony put it nicely when she said “Any argument for moral scepticism will be based upon premises which are less obvious than the existence of objective moral values themselves.”[2] If she is right then it seems like the Moorean response works as well here as it does anywhere.
Objections
One popular objection to the second argument I presented, which I hear surprisingly often, is that in our empirical experiences we can achieve a reasonable consensus about what the physical world is really like, but our moral experiences are less conspicuous, less clear, ‘fuzzier,’ and are less conducive to creating consensus about the fabric and structure of moral reality. This, it is suggested, gives us at least one reason to think that we should place more confidence in our empirical experience of the noumenal external world than we should place in our moral experience. Our moral experiences are more suspicious because they are a great deal vaguer than our empirical experiences.
I have two responses to this. First, although not all scientific matters can be adjudicated by empirical experiments either (think, for instance, of empirically equivalent scientific theories in equally good scientific standing, such as the neo-Lorentzian view of relativity, and the standard view of relativity), I will grant (and not just for the sake of argument) that scientific consensus is more easily reached than moral/ethical consensus. However, I want to note in passing that nearly everyone (who is some kind of moral realist) agrees that it is wrong to (without a justifying reason) kick a pregnant woman in the stomach repeatedly for amusement. There is, I think, a great deal more moral consensus than people typically imagine, but I digress. Having admitted this point of disanalogy, it still looks to me as though moral realism is so nearly as well justified as belief in the noumenal external world that the disanalogy makes no practical difference; moral realism ought still to be believed in the absence of a defeater, or else, on pain of inconsistency, we will be putting our belief in the external world in the very near occasion of philosophical abandonment.
My second response is to say that I think this objection confuses moral realism with particular meta-ethical accounts, or normative accounts. The arguments presented are not suggesting that we should be able to discover, through moral experience, what is objectively morally right (or wrong) with as much clarity and consensus as we discover what is objectively scientifically right (or wrong). What is being claimed is merely that in our moral experience we are as sure that we are being confronted with some set of objective moral facts as we are that, in our empirical experience, we are being confronted with an external world. The point here is that moral experience leads us to be confident not in any particular moral theory (eg. Utilitarianism, Egoism, Deontology, etc.), but in moral realism itself, a presumption which all moral theories share in common, and on which their coherence depends.
[1] See James Lenman, “Moral Naturalism,” inThe Stanford Encyclopedia of Philosophy ed. Edward N. Zalta, (2014). http://plato.stanford.edu/archives/spr2014/entries/naturalism-moral/
Tyler Journeaux 
Is apophatic naturalism an option? (j/k.) Anyways, even some divine command theorists consider DCT to be an anti-realist positions—Thomas Carson, and Linda Zagzebski (I think). David Baggett makes the remark that most DCTists rightly limit DCT to issues of moral obligation. Baggett thinks theistic ethicists needs to something like natural law theory or platonism for values. https://youtu.be/pV6ez6QwGGQ?t=604
On moral epistemology, realists can think of it like knowing math, or like a perception. I think realists usually pick one or the other. Michael Huemer, the moral intuitionist says “That is, an intuition that p is a state of its seeming to one that p that is not dependent on inference from other beliefs and that results from thinking about p, as opposed to perceiving, remembering,
or introspecting (2005).” For a perceptual account, see http://plato.stanford.edu/entries/fitting-attitude-theories/#SenThe and note some disanalogies between value perception and color perception.
I agree with the basic idea that if something seems to you to be the case, then you have some prima facie justification for it. (This is something like phenomenal conservatism or the principle of credulity.)
But, as you say, subjective idealists will not be impressed by the Moorean response. Similarly, moral anti-realists will not be impressed. Craig notes that the reality of temporal becoming is even more obvious than the external world. We could deceived about the external world by being brains in a vat, but the changing contents or our consciousness is enough for temporal becoming. I suspect the B-theorist is already aware of this and is unimpressed. Similarly, 1+1=2 is plausibly properly basic, but anti-realists will refrain from saying that it is literally true. Surely, the Moorean response will be dialectically ineffective against them.