 A priori justification is a type of epistemic justification that is, in some sense, independent of experience. Gettier examples have led most philosophers to think that having a justified true belief is not sufficient for knowledge  (see Section 4.4, below,  and the examples there), but many still believe that it is necessary. In this entry, it will be assumed, for the most part, that even though justification is not sufficient for knowledge it is necessary and that a priori knowledge is knowledge based on a priori justification. So much of the discussion will focus on a priori justification.