The propositional attitude by which Socrates explained his remaining in prison was a belief (doxa): the belief that to do so would be for the best. Aristotle ventured a correction. Socrates remained in prison because he chose to; but he ‘can hardly be said’ to have believed to (cf. Aristotle (4), III, 1112a 4–5). Since no belief is necessarily acted on, actions cannot be explained solely by their agents’ beliefs. Propositional attitudes of some other kind must be at work: attitudes the natural behavioural expression of which is trying to bring about (cf. Anscombe (1), 68). Aristotle’s generic term for such attitudes was ‘orexis’ which the medieval Aristotelians rendered into Latin as ‘appetitus’. In revising the Oxford translation of Aristotle, Jonathan Barnes has followed their example, rendering it as ‘appetite’.