In the Fifth Meditation Descartes considers the problem of knowledge preservation : the challenge of accounting for the diachronic certainty of perfect knowledge [scientia]. There are two general solutions to PKP in the literature: the regeneration solution and the infallible memory solution. While both readings pick up on features of Descartes’ considered view, I argue that they ultimately fall short. Salvaging pieces from both readings and drawing from Descartes’ virtue theory, I argue on textual and systematic grounds for a dispositionalist (...) solution. On this view, the diachronic certainty of scientia is achieved through virtuous habits of belief. (shrink)