Abstract

‘Skepticism’ refers primarily to two positions. Knowledge skepticism says there is no such thing as knowledge, and justification skepticism denies the existence of justified belief. How closely the two views are related depends on the relationship between knowledge and justification: if knowledge entails justified belief, as many theorists say, then justification skepticism entails knowledge skepticism (but not vice versa). Either form of skepticism can be limited in scope. Global (or radical) skepticism challenges the epistemic credentials of all beliefs, saying that no one knows anything, or no belief is justified. More local skepticism is restricted to some domain; thus some skeptics question the epistemic credentials of beliefs about other minds (but not beliefs about one’s own mind), or beliefs concerning empirical matters (but not concerning a priori matters).