Evolutionary debunking arguments use the evolutionary origins of our moral attitudes to argue that our moral beliefs are not explained by realistically construed moral facts, and that our moral beliefs are therefore unjustified. Third-factor replies to debunking argument rely on substantive moral claims to argue that, even if our moral beliefs are not explained moral facts, they are explained by some third-factor that also explains those moral facts. This is supposed to show that our moral beliefs can be justified even (...) given the debunker’s evolutionary genealogy of those beliefs. In this paper I argue that third-factor replies fail. First, I argue that our belief is defeated if we withhold belief that it is explained by the fact that makes it true or by some third-factor that also explains that fact. I then argue that the third-factor replier cannot consistently take our beliefs about basic moral principles to be explained by some such third-factor because of the concession they make in response to debunking arguments and the meta-ethical view they are looking to defend. This implies that the third-factor replier’s beliefs about basic moral principles are defeated. Furthermore, we cannot take non-basic moral beliefs to be explained by some such third-factor if we withhold our basic moral beliefs, and so the third-factor replier’s non-basic moral beliefs are also defeated. Thus, the third-factor replier ought to withhold their moral beliefs in response to debunking arguments and, because their arguments rely crucially on moral claims, those arguments fail. (shrink)

According to one influential response to evolutionary debunking arguments against moral realism, debunking arguments fail to undermine our moral beliefs because they fail to imply that those beliefs are insensitive or unsafe. The position that information about the explanatory history of our belief must imply that our beliefs are insensitive or unsafe in order to undermine those beliefs has been dubbed “Modal Security”, and I therefore label this style of response to debunking arguments the “modal security response”. An alternative position, (...) that our beliefs can be defeated if we accept those beliefs are not explained by the relevant facts, I call “explanationism”. In this article, I argue against Modal Security in favour of explanationism. First, I present two examples from the literature that appear to support explanationism, and I argue that these examples imply that the modal security response is fundamentally misguided about the nature of epistemic defeat. I then consider a recent response from Justin Clarke-Doane and Dan Baras, who claim that examples of this kind fail because they are either incoherent or involve a failure of modal security. I argue that, due to their position on the failure of evolutionary debunking arguments, Clarke Doane and Dan Baras are committed to the existence of coherent, sufficiently simple examples that can help us arbitrate between explanationism and modal security. I then construct such an example and argue that it clearly indicates that we should reject Modal Security in favour of explanationism. This implies the modal security response to debunking arguments fails. (shrink)

Evolutionary debunking arguments claim that the evolutionary origins of our moral beliefs imply that those beliefs cannot be justified under the assumption of moral realism. In chapter one I outline three prominent evolutionary debunking arguments in the literature, and in chapter two I outline two types of “minimalist” replies to debunking arguments. These replies grant that our moral beliefs are not explained by the moral facts and then rely on substantive moral claims to show that our moral beliefs might still (...) be reliable. One way of objecting to these minimalist responses is to claim that the explanatory disconnect implied by debunking arguments defeats our moral beliefs, and so minimalist replies are not entitled to rely on substantive moral claims once they have granted this explanatory disconnect. In chapter 3 I argue that information can undermine our beliefs even if does not imply that our beliefs are modally insecure, and that this removes one way that the minimalist might deny that the explanatory disconnect implied by debunking arguments defeats those beliefs. In the next chapter I argue for a specific explanatory constraint on belief:. I point out, however, that according to, EDAs do not, by themselves, establish the explanatory disconnect that defeats our belief. In chapter five I supplement EDAs with my own arguments which, when combined with EDA’s, establish that our moral beliefs are defeated according to. When EDAs are combined with these arguments, minimalist replies fail because they crucially rely on defeated moral beliefs. In the final chapter, I consider and reject a potential avenue of response by the minimalist, and considering this response sheds further light on the kind of attitude we can have towards our belief that defeats that belief. (shrink)