Abstract
The article examines the Socratic principle that (1) virtue is knowledge and its corollary that (2) nobody errs voluntarily (nemo sua sponte peccat). It tries to show (I) that both principles are paradoxa, i.e. from a phenomenological point of view, they seem to be false; (II) that nevertheless the platonic Socrates accepts both principles as true; and finally (III) that these principles are analytical truths a priori which can only be understood if a person (soul) finds them in him- or herself.