Aristotelian Practical Reason

Abstract

can readily be converted into a statement of someone's reason for acting: 'He took the medicine because he wanted to be healthy and thought that if he took it he would be healthy.' Aristotle used the notion of a 'practical syllogism' to make this connection. In De Motu chapter 7 he used the practical syllogism to explain reasons for acting and in Nicomachean Ethics, Books 6 and 7 he used it in discussing practical reasoning. (I am aware that in saying this I am using the term 'practical syllogism' in a wider sense than is favoured by some writers, for instance Hardie and Cooper. I shall return to this issue at the conclusion.) Sometimes there is practical reasoning which does not lead to action, as in weakness of will (EN Bk. 7). In this case the practical reasoning does not supply the reasons for the action performed. Conversely, there can be a reason for acting without any reasoning (MA ch. 7, 70Ia3Iff.). In order to understand Aristotle's account we need to look at what is common to both practical reasoning and reasons for acting and at what is peculiar to each.