Abstract
In this paper I propose an indubitability analysis of knowledge. The motivation for this analysis is a conviction I have that the Cartesian analysis of knowledge as indubitability is not completely mistaken, although it requires considerable weakening if it is to be satisfactory. My analysis may be contrasted to those which treat knowledge as a species of the genus justified true belief. For although on my analysis, ‘S knows that p’ entails ‘S has a justified true belief that p’, I am not proposing indubitability as a differentia distinguishing knowledge from other members of the genus justified true belief. The situation here is analogous to that of the conceptual relation between vermillion and red: ‘X is vermillion’ entails ‘X is red’, but there is no straightforward differentia which would entitle us to think of vermillion as a species of the genus red. Another point of contrast is that species-of-justified-true-belief analyses start with an analysis which is too weak and strengthen it. My starting point is an analysis which is too strong which I then weaken.