Abstract

An increasingly common form of naturalism associated with the study of morality is what might be called “scientific naturalism,” which takes as its subject matter various empirical phenomena associated with talk of “morality” and aims to subject them to scientific inquiry, just like any other empirical phenomena. This is unproblematic when it comes to scientific investigations into the origins of the human capacity for normative guidance or moral emotions, or the neurophysiology associated with moral feeling and behavior, but things get much more complicated when it comes to the project of explaining our moral beliefs. It is, of course, an empirical phenomenon that we hold the moral beliefs we do, so it may seem obvious that this too can be causally explained using scientific tools. But, while there is room for scientific inquiry into causal factors, such as evolutionary influences, that have plausibly helped to shape many moral beliefs to some degree, it is a mistake to assume that our moral beliefs across the board can best be explained through appeal exclusively to scientifically accessible causes. This scientific naturalist exclusivity assumption is in fact deeply problematic, overlooking (or prematurely dismissing) the possibility that at least many of our moral beliefs are best explained through our grasping of good reasons for them – considerations we correctly understand as justifying them, though this is not something that shows up in scientific causal explanations. It is easy to miss this point about the potential role of the appreciation of justification by the believing mind when considering moral judgments simply from the external perspective of an amoral anthropologist, but it becomes clear when taking up the internal perspective of the committed moral agent, as when thinking about why we ourselves believe that human trafficking is wrong. This matters because, while science is invoked by those who purport to provide “debunking explanations” of our moral beliefs across the board (showing them to result simply from causal factors insensitive to any objective moral facts), they are actually relying on the scientific naturalist exclusivity assumption, thus begging the question against their opponents, who hold that we have knowledge of objective morality as a result of grasping good reasons for it. I explore these complexities surrounding the explanation of our moral beliefs and argue that while the picture advocated by debunkers remains a possibility, it is certainly not established by science, and recent arguments purporting to debunk the idea of knowable, objective morality fail.