Morgan asked:

Today, we think that slavery is wrong and barbaric although once it was considered perfectly acceptable. Is it possible that in the future something we think is OK now will be judged in the same way? any examples you can think of??

Answer by Massimo Pigliucci

The answer to this question hinges on the concept of moral progress, and hence on the whole discussion between moral objectivists and relativists. If one thinks that morality is entirely culturally relative and arbitrary — something, say, akin to etiquette — then one cannot possibly defend the idea that slavery is wrong in general. It may be considered wrong by our society today, but we have no grounds to think it wrong in any other society or at any other time.

Few philosophers, I surmise, subscribe to that sort of relativism. And most people today — philosophers or not — would probably agree that ‘slavery is wrong’ is a bit more powerful a statement than ‘the dinner knife ought to be placed on the right of the plate.’ The trouble, of course, is that it has proven remarkably difficult to unpack and rationally defend the idea of objective morality, at the least in the strong sense of the existence of mind-independent moral truths somewhere ‘out there’ (a position referred to in meta-ethics as moral realism).

But one does not need to go far to be able to agree that slavery is wrong in a robust sense of the term ‘wrong.’ Ethics, after all, is a way of thinking about the acceptability (or not) of certain actions within the context of human societies. That acceptability can be based on a number of criteria, but these usually include the utilitarian preference for reducing suffering and increasing ‘happiness’ (broadly construed), as well as the virtue ethical requirement to live virtuous (i.e., characterized by equanimity, justice, courage, etc.) lives and to put in place societal conditions that foster human flourishing (again, broadly construed — what the ancient Greeks called eudaimonia).

In this context, then, ethics becomes a type of practical reasoning of the ‘if… then’ type, which begins with certain premises (if X is the case…) and attempts to arrive at logically entailed conclusions (… then Y will also be the case). For instance, from the premise that human flourishing is a valuable goal one can immediately derive that slavery is, therefore, wrong, because it clearly hampers the flourishing of the slaves, under pretty much any reasonable conception of flourishing.

Of course, as in any instance of logical reasoning, one could reject the premise — in this case, that we should value human flourishing. But that move would then require replacing it with some other acceptable premise from which to derive the conclusion that slavery is not morally wrong. For instance, someone could say that whoever can impose by force the subjugation of another human being has the right to do so, from which it would indeed follow that slavery is morally good. Notice first, however, that the same person would have then to allow the (logical) possibility that he himself may one day become a slave, if he encountered someone who had more coercive force at his disposal and used it to impose his will. Second, and fortunately, most of us actually reject this alternative premise and consider someone who would defend it as a sociopath (in the technical sense of the term: a person with a diminished ability to empathize with other human beings, especially the slaves).

The second part of the question concerns possible examples of behaviors that are currently deemed acceptable but will likely, in the future, be regarded just as immoral as we regard slavery to be. I think there is a number of such examples, but an obvious one that comes to mind is our treatment of animals for food consumption. I am not a vegetarian, and even less a vegan, but I do try to be what you could call an ‘ethical omnivore’: I potentially eat anything, but I do concern myself with where my food comes from, and in particular with its environmental and ethical impact.

If I were a utilitarian, like my colleague Peter Singer, I could justify my concern for the treatment of animals on the basis of the fact that it increases overall suffering in the world (namely, that of the animals in question!) while increasing overall happiness only marginally (through the pleasure experienced by those who eat the animals). As a virtue ethicist, instead, I think that it is a sign of a bad moral character to impose suffering on other sentient beings (be they human or not) for the sake of one’s own aesthetic and sensory pleasure. Either way, it amounts to the same result, and I am convinced that future generations will increasingly see it that way, and will therefore be surprised at our inability as a society to recognize the point, just like we are surprised at the inability of previous societies (or, indeed, of some current ones!) to recognize that slavery is wrong.