In this dissertation I discuss the epistemology of ethical intuitionism, in particular the claim that mature moral agents possess self-evident moral knowledge. Traditional intuitionists such as W.D. Ross have claimed that by reflection, we can acquire knowledge of our basic moral duties such as the duty of veracity or benevolence. Recent defenders of intuitionism such as Robert Audi have further developed this theory and argued that adequate understanding can be sufficient for moral knowledge. I criticize this view and argue that (...) such accounts fail to make a convincing case for a foundationalist moral epistemology. Instead, I propose to separate the question of how we acquire moral knowledge from an account that justifies moral beliefs. In response to the first issue, I draw an analogy between our moral intuitions and chosmkian linguistics; in both areas, I argue, human beings possess a universal, unconscious and (partly) inaccessible system of rules that explains how we come to learn language and to make moral judgments. In regards to the justificatory issue, I address recent evolutionary debunking arguments designed to undermine the claim that our moral judgments track stance-independent truths. I try to show that this conclusion only follows under the assumption of an instrumentalist interpretation of moral reasoning which the intuitionist is not forced to accept. (shrink)