A range of extremely plausible moral principles turn out to generate “deontic cycling”: sets of actions wherein I have stronger reason to do B than A, C than B, and A than C. Indeed, just about anything recognizable as commonsense morality generates deontic cycling. This matters for two reasons. First, it creates a problem for the widely held view that agent-centered rankings can square consequentialism with commonsense morality. Second, it forces a choice between some deeply plausible views about rationality—wherein someone (...) cannot have stronger reason to do A than B, B than C, and C than A—and commonsense morality. (shrink)

Most promising responses to skepticism fall into “Moorean” or “rationalist” camps. Mooreans believe that some apparently circular forms of reasoning allow us to have justification to believe that skeptical hypotheses are false. Rationalists believe that we have a priori justification to believe that skeptical hypotheses are false. It can seem that anti-skeptics are stuck choosing between fishy circular reasoning and mysterious a priori justification. I present a new difficulty for rationalism by focusing on skeptical scenarios wherein our faculties of a (...) priori reasoning are untrustworthy. In dealing with these scenarios, rationalists end up having to embrace the same sorts of circular reasoning that Mooreans use to deal with more familiar skeptical scenarios. As a result, there is no viable diagnosis of what's wrong with Moorean reasoning that does not also apply to rationalism: both anti-skeptical approaches are in the same boat when it comes to embracing circular reasoning. (shrink)

Few philosophers believe that G. E. Moore's notorious proof of an external world can give us justification to believe that skepticism about perceptual beliefs is false. The most prominent explanation of what is wrong with Moore's proof—as well as some structurally similar anti-skeptical arguments—centers on conservatism: roughly, the view that someone can acquire a justified belief that p on the basis of E only if he has p-independent justification to believe that all of the skeptical hypotheses that undermine the support (...) lent by E to p are false. In this paper I argue that conservatism does not make trouble for Moore's proof. I do this by setting up a dilemma concerning the notion of "justification to believe" that figures in conservatism. On one understanding of justification to believe, conservatism is subject to obvious counterexamples. On another understanding of justification to believe, conservatism is consistent with Moore's "proof conferring justification upon its conclusion. Since these two understandings exhaust the logical space, the conservative indictment of Mooreanism fails. (shrink)