There were a few arguments brought up in the last moral realism thread which I wish to address in an organized fashion. The arguments I will consider are, as I label them, the argument from social evolution, the argument from irrationality, and the argument from queerness—that last one sounds funny, but it’s actually the real name of the argument in the metaethics literature. All of these arguments purport to show that some aspect of the picture underlying moral realism is flawed, and hence that it should be abandoned. For the most part the posters I associate with these arguments are: Darthmix and Qingu with social evolution, Morninglord with irrationality (edit: it turns out I was wrong), and Violent Chemistry and Incenjucar with queerness. Apologies if I missed or mischaracterized you.
First, I will consider the argument from social evolution. Social mores, this argument goes, contribute to the competitive fitness of a society, and hence over time are subject to the same lawlike generalizations that govern physical adaptation in species. From this, we can conclude that the content of our moral opinions is determined by selective pressures rather than rational argument and access to moral facts.
There are two major problems unique to this argument. The first is that it’s unclear how well the analogy with selection pressures on genes actually applies to moral opinions. Some preliminary problems: what consitutes a ‘society,’ as taken to be an object of selection? A school district? A family? A country? What counts as sexual reproduction? What are the selective pressures? What counts as mutation? How do we count and isolate discrete moral opinions such that they are competing with one another? How do we individuate moral opinions from other sorts of opinions? The analogy between genetic evolution and cultural evolution may seem appealing on the face of it, however, it is not at all clear how to nail down any of the specifics. And if the specifics can’t be made to match, then it’s not clear that moral ideas really will be governed by the same sort of lawlike generalizations as genes.
The second problem for this argument is that it relies on a problematic appeal to exclusion. The appeal is thus: if moral ideas are governed by lawlike generalizations such that we can predict their change over time only by reference to certain social facts, then it is not the case that moral ideas are discovered through rational investigation. I call it an appeal to exclusion because the fact that moral ideas are governed by lawlike generalizations in the social sciences is supposed to exclude them from also being the product (or possible product) of rational investigation. However, this is not necessarily the case. Consider my action of drinking a glass of water when I’m thirsty. This action can be explained as an instance of rational action and goal fulfillment. It is also the case that it can be (in principle) predicted entirely by reference to the physical states of the matter making up my body and immediate surroundings. So, the fact that the matter making up my body is governed by a set of physical laws such that its behavior is entirely predictable on those grounds alone does not threaten the fact that those very same actions can be the product of rational thought. There need to be additional reasons to suppose that not only are our moral ideas governed by social science laws, but they are also not (and can not be) the product of rational investigation.
That brings us to the argument from irrationality, as supplied by Morninglord. I take this quote to exemplify it:
“There's a lot of evidence that people don't really so much choose to do anything socially, as be mutually influenced. The idea of rational decision making is, unfortunately, a fallacy when it comes to everyday life. It works in very academic, structured, trained disciplines, but everyday people don't do it.”
This, on the face of it, gives us good reason to think that moral ideas cannot be the product of rational investigation. After all, if there is no such thing as rational investigation, then how could moral ideas be the product of it? Of course, I cannot give thorough commentary without being familiar with the literature in question. I am initially skeptical, however, not that such literature exists, but that the experiments in question clearly support a conclusion that would be threatening to the person believing in moral facts. Interpretation of the results is, in itself, a philosophical endeavor—especially when you get into things like trying to decide what counts as rational decision making.
But even beyond that, the believer in moral facts need not suppose that everyday people engage in detailed moral reasoning every time they are presented with a decision. In fact, I think that few philosophers would contend that ordinary people give their beliefs the same rigorous analysis that ethicists do. The moral realist need only suppose that there are moral facts and that they can be uncovered through the academic, structured, trained reasoning that ethicists engage in, and furthermore, that if one is interested in bringing one’s self into line with moral facts that they should follow the results of that sort of reasoning.
Finally, we have the argument from queerness, due to Mackie, wherein the objection is that moral facts would have to be very metaphysically queer in order to exist, and hence that we should think they don’t. I’m going to copy a passage from a paper of mine wherein I explain the argument from queerness:
Mackie’s error theory consists in two related claims. The first is the conceptual claim that our concept of morality is the concept of an objective, prescriptive, categorical fact. The second is an ontological claim that there are no such facts. In essence, our moral discourse presupposes a type of thing which doesn’t exist, and hence assertions within that discourse are uniformly false. This diagnosis could be understood analogously to a modern evaluation of the medieval discourse on witches—since there is no such thing as a witch, all the historical assertions on witches, from “witches cast hexes” to “witches can’t make broomsticks out of pine trees” are systematically false. For any of them to be true there would have to be witches, and there are no witches.
So, what is an objective, prescriptive, categorical fact? A fact is prescriptive if it tells us what to do, and prescribes a course of action. Furthermore, a fact is categorical if it applies regardless of our particular motivations. For example, I can’t release myself from a categorical obligation to donate to charity by citing my desire to save money. Finally, a fact is objective if it somehow exists out there in the universe, independent of human inclination, and ready to be perceived and interacted with.
Why are there no such facts? Mackie raises two objections, one metaphysical and the other epistemic. In the metaphysical objection he likens the existence of an objective, prescriptive, categorical fact to the existence of the Platonic form of the good. Such a fact, he holds, would have to be intrinsically motivating to everyone who came into acquaintance with it, and its existence would entail that there were states of affairs which intrinsically had the demand for a certain action. There would have to be states with to-be-pursuedness somehow built into them. But this isn’t something we ever find in the world—the states we are acquainted with are inert, and have no such baggage.
His epistemological objection is closely related. Our normal conception of perception doesn’t account for how we could come to know the moral baggage of any particular state of affairs. Hence, even if we posit such metaphysically queer stuff as states with to-be-pursuedness intrinsically built in, it’s still unclear how we could ever come into contact with and know their moral baggage.
Due to the metaphysical and epistemic worries about objective, prescriptive, categorical facts, Mackie concludes that there are no such things, and furthermore, that our moral discourse must thus be uniformly false.
This is similar to the arguments put forward by Violent Chemistry and Incenjucar. Moral facts do not exist because they require a sort of magic that simply doesn’t occur in the world. Now, of all the above objections I find this one to be the most significant, and I am not entirely happy with the state of my response.
My response is, in essence, that Mackie’s error theory entails nihilism. Our day to day experience gives us overwhelming evidence that nihilism is false. In fact, it’s much more plausible to believe that nihilism is false and Mackie’s argument hence contains some flawed thinking than it is to believe that nihilism is true and Mackie’s argument is correct. Hence, I believe that nihilism is false and so is Mackie’s argument for error theory.