This dissertation develops and defends the claim that our epistemic access to
moral properties is grounded in a posteriori perceptual experiences. It is divided into
two parts. In part I, I present the epistemic access problem for realist moral
epistemology, and then argue against several a priori attempts to resolve the problem. I
begin by defending an understanding of evolutionary debunking arguments according
to which the problem is grounded in a lack of epistemic access to sui generis, non-causal
moral facts. Next, I argue that even the most sophisticated versions of reflective
equilibrium fall victim to the “garbage in, garbage out” objection which besets
coherentist theories more generally. I then survey the most influential other a priori
approaches to epistemic access. I conclude that each of them is victim to some variation
of the same dilemma: Either they fail to ensure epistemic access, or they succeed by
providing epistemic access to the wrong properties—viz. not the robustly normative
ones.
In part II, I defend a wholly a posteriori moral epistemology according to which
our epistemic access to the moral properties is via perceptual experience. I begin with a
positive argument that moral properties figure in the contents of perceptual experience,
making use of the “method of contrast” found in the philosophy of perception
literature. Next, I defend the foundationalist credentials of the perceptualist view in
light of the objection that moral experiences will be epistemically dependent on prior
background (moral) beliefs. I claim that the epistemic dependence of these moral
experiences depends on the nature of influence the prior beliefs have and that the
influence is not of the problematic sort. I then discuss the role of emotions in generating
moral perceptions. I argue that emotions play an essential role in moral perceptual
experiences, but that this is compatible with foundationalism and perceptualism.
Finally, I return to the issue of epistemic access, arguing that the perceptual view
provides an explanation of our epistemic access to the moral properties.
