In his book Roman Law: Linguistic, Social and Philosophical Aspects (Edinburgh, 1969), Professor Daube proposes a heterodox interpretation of Aristotle's distinction in EN v 8 between two sorts of ἁμαρτήματα: ἁτυχήματα, mishaps, and ἁμαρτήματα proper, mistakes. Mr Crook, in his review of the book (CR n.s. xx (1970), 363), has already taken issue with the main point of this interpretation. In what follows I hope to clinch the verdict for orthodoxy, while ceding to Daube a point of broader significance.

Aristotle characterizes ἁμάρτημα as a sort of injury committed ‘in a transaction’ (as we might say, by one private person against another), involving ignorance on the agent's part about some particular circumstance of his action (1135 b 11–16). He calls this class of injury ἁμάρτημα because he holds that inasmuch as the agent did not know what he was doing, to that extent he did not mean to do what he did (cf. 1135 a 23–32).