Are There More than Minimal A Priori Limits on Irrationality?

John Biro and Kirk Ludwig

Abstract

The authors criticize Stephen Stich's argument, in chapter 2 of The Fragmentation of Reason, that there are only minimal a priori requirements on the rationality of intentional agents. Stich attempts to undermine arguments for strong a priori limits on irrationality in the interest of the ‘reform-minded epistemologist’, who aims to improve our cognitive practices. The article shows three things: first, that Stich's arguments against strong a priori limits on how badly a person can reason are unsuccessful; second, that the position Stich argues for, on the basis of Grandy's principle of humanity, turns out not to be distinct from the one he rejects; third, that the position that Stich rejects in order to preserve some scope for improving our reasoning is not only no danger to that project but must be presupposed by it.