Taking the Helm: Genealogical Debunking Arguments, Moral Realism, and the Possibility of Moral Knowledge

Genealogical debunking arguments aim to show that, given their provenance, none of our moral beliefs are justified, at least assuming moral realism. In particular, they claim that this is so because the best, complete explanation of why we hold the moral beliefs we do neither presupposes nor entails their truth. I dispute this explanatory claim, suggesting instead that, in at least some cases, the best explanation of our beliefs must appeal to our capacity to acquire moral knowledge through reflection. To defend this suggestion, I respond to three different rejoinders debunkers might offer. One of these contends that the proposed explanation is redundant: if we want to explain why someone judges some action wrong, all we need to know is the character of their moral sensibilities. Two other rejoinders appeal to general skeptical challenges. According to the first, if realism is true, the evidence available to us in reflection necessarily underdetermines the truth of our ethical beliefs. Like the so-called Benacerraf-Field challenge to mathematical platonism from which it derives, the second challenge involves two distinct charges: first, that knowledge requires there be a causal or explanatory connection between our beliefs and the facts that realism precludes, and second, that realists cannot explain our reliability in ethics. Making novel use of Ludwig Wittgenstein’s remarks about following rules, I argue that that each of the first two rejoinders rests on a confused view about the ways we are liable to go wrong in ethical reflection. In response to the third rejoinder, I argue that while the no-accident condition on knowledge is indeed best understood in explanatory terms, realism does not preclude the possibility that our beliefs might satisfy this condition on knowledge; in addition, I explain how realists can explain our reliability in ethics. In all of these cases, moreover, I suggest that the responses I outline are open only to proponents of a deflationary form of realism that, following Amie Thomasson, I call “simple realism,” conceding to debunkers that their arguments are likely unanswerable by proponents of more inflationary or so-called “robust” forms of realism