The word “picture” occurs pervasively in Wittgenstein's later philosophy. Not only does Wittgenstein often use literal pictures or the notion of mental pictures in his investigations, but he also frequently uses “picture” to speak about a way of conceiving of a matter (e.g. “A picture held us captive” at Philosophical Investigations§115). I argue that “picture” used in this conceptual sense is not a shorthand for an assumption or a set of propositions but is rather an expression of conceptual bedrock on the model of an organising myth. This reading builds primarily on work by Gordon Baker and Stanley Cavell.