Abstract: It seems that if a thinker in an argument arrives at an empirical conclusion, then some of the belief-formation or reasoning principles she employs must be a priori if the reasoning is to be knowledgeable. Stewart Shapiro accepts this claim, and investigates the way in which the basic principles of logic must have an a priori status if the process of empirical confirmation of propositions reasoning that involves such principles of logic is to make sense.

Keywords: a priori, empirical confirmation, logic, reasoning, Stewart Shapiro,