Virtue epistemology standardly divides into two camps: virtue-reliabilism and virtue-responsibilism. This chapter discusses the epistemic warrant in terms of features of reliable belief-forming faculties. By treating epistemic virtue in terms of functions, and functions in terms of history, it sets out to understand functions, virtues, and warrant. The chapter explicates the etiological functions. The etiological account of functions entails an account of normal functioning and normal conditions. On the etiological account, functions arise when an item produces a beneficial effect that in turn enters into a feedback mechanism, where the mechanism explains why the item persists or reoccurs because of the beneficial effect. The chapter identifies three functional norms for any item with an etiological function: function fulfillment, normal functioning, and function fulfillment because functioning normally. Natural selection requires three elements: variation, copying, and beneficial consequences. Trial-and-error learning involves trials, variations in behavior, errors, negative reinforcers and successes, positive reinforcers.

Epistemologists and non-philosophers find the Moorean reasoning unattractive. It is not easy to locate the source of this dissatisfaction, however. This chapter argues that it arises from requirements of responsibility that apply to rational agents in the course of conscious reasoning or deliberation. Dogmatism alone isn't enough to evade standard arguments for skepticism about the external world. Warrants are things of a type that is suited to play the role of normative epistemic reasons in an agent's deliberations about what to believe. A person might have a warrant to believe a particular proposition, believe that proposition, and yet not hold that belief in a reasonable, epistemically appropriate, or epistemically satisfactory way. The external world skeptic holds that no one is doxastically justified in believing anything about the external world by means of the senses. The Moorean dogmatist diagnoses this skeptical claim as arising from a principle about experiential warrant.