Description
In this thesis, I examine the structure of epistemic justification and defend a theory of epistemic justification termed "infinitism." The structure of justified belief is commonly analyzed by beginning with skeptical challenges to justification. Keeping with this method, I begin my argument for infinitism by examining a skeptical challenge termed "the regress paradox." I argue that infinitism is the only theory of epistemic justification that can solve the paradox, which entails that ceteris paribus infinitism is preferable to other theories of epistemic justification. I then examine an argument against infinitism called the modus ponens reductio, which is countenanced by several philosophers as their main reason for rejecting infinitism. I argue that the scope of the reductio is mistaken: the reductio (slightly modified) applies to the leading epistemic theories of justification as well as infinitism. Thus, I show that the reductio is a general skeptical problem for all theories of justification to face. This shows that the leading epistemic theories of justification are not preferable to infinitism since the reductio (slightly modified) applies to them as well and because infinitism is the only theory that can solve the problem of regress. However, if the reductio is correct, it might seem that either infinitism or skepticism (i.e., only few, if any, of our beliefs are justified) is correct. To support infinitism, I present a solution to the reductio, which shows that it is not a problem for any theory of epistemic justification. The reductio should therefore not convince us of skepticism. Since the reductio is the main reason for rejecting infinitism and since infinitism is the only theory that can solve the regress paradox, I conclude that epistemic infinitism provides the most tenable account of justified belief, and we therefore ought to justify our beliefs according to the infinitist structure of justification