Volume 90, Issue 2, April 2013
Thomas D. Senor
Justified Belief and Demon Worlds
The New Demon World Objection claims that reliabilist accounts of justification are mistaken because there are justified empirical beliefs at demon worlds—
worlds at which the subjects are systematically deceived by a Cartesian demon. In this paper, I defend strongly verific (but not necessarily reliabilist) accounts of justification by claiming that there are two ways to construct a theory of justification: by analyzing our ordinary concept of justification or by taking justification to be a theoretic term defined by its role in the theory of knowledge. The former route is not promising because of the splintered nature of our ordinary concept of justification—or perhaps because there is no single such concept. On the other hand, if justification is defined by the role it plays in the theory of knowledge, then there is good reason to think that justification must be strongly truth-conductive since the term was introduced by Edmund Gettier to play the primary role in converting true belief into knowledge. And if that is right, then there will be no justified empirical belief at demon worlds. The real lesson of the demon world is then turned on its head: justification does not supervene on what one shares with one’s deceived doppelganger.