Abstract

In everyday life, we often understand skepticism as a position that one may set aside because of its absurdity or incoherence. In Greek philosophy, skepticism was rather an inquiring attitude that led to the suspension of judgment and, as a result, the freedom from distress. In Modern philosophy, many philosophers viewed skepticism as a phase of thought that had to be overcome before laying firm foundations for the sciences. These pictures differ from the outlook that dominates current analytic epistemology, where skepticism has normally been understood as a series of paradoxes that arise when we reflect on the workings of ordinary epistemic concepts like KNOWLEDGE and EPISTEMIC JUSTIFICATION. A skeptical paradox emerges when we identify a condition that seems to be necessary to have knowledge or epistemic justification, while it also seems that that condition cannot be met. This chapter explains why the picture of skepticism as a series of paradoxes is central to contemporary analytic epistemology and identifies some of the main features of skeptical paradoxes about the external world. After identifying two types of replies, it presents two influential paradoxes based on the closure and underdetermination principles, identifies some relevant differences between the two paradoxes, and critically examines some attempts at solving them.