This title sheds light on Wittgenstein?s third masterpiece: ?On Certainty?. It clarifies his ultimate thoughts on basic beliefs and his rebuttal of scepticism. Disentangling the apparent knots in the work, Moyal-Sharrock elucidates Wittgenstein?s rejection of the traditional view of basic beliefs as basic ?prepositions?, and his account of our foundational certainties as nonepistemic, ?nonpropositional? attitudes that, as such, have no verbal occurrence but manifest themselves exclusively in our actions. This ?logical pragmatism? is seen as dissolving the logical incommensurability between belief and action.