Introduction: The Old Rationalism and the New Rationalism

Abstract

The philosophical debate about the possibility of authentic a priori knowledge, that is, non-stipulative, non-trivial knowledge of the way the world necessarily is, obtained sufficiently independently of any and all sense-experiential episodes and/or contingent natural facts, is no less important today than it was when Plato posited in the Meno that we are able to have such knowledge owing to a pre-natal close encounter that our disembodied souls had with the Forms, and when Descartes posited in the Meditations on First Philosophy that such knowledge is infallible because guaranteed by a non-deceiving God. Of course, neither the platonic story nor the Cartesian story about our purported a priori abilities has many adherents today. Nevertheless, a large majority of philosophers (71.1 percent, according to a recent PhilPapers survey1) do indeed believe that a priori knowledge is really possible.