This chapter argues that the play's debt to classical sources is much greater than has been hitherto supposed, and that understanding this inheritance allows us to give an interpretation of the work which dissolves difficulties that have long disturbed commentators. It takes the Duke at his word, and argues that he really does want to rethink our whole concept of what goodness – and hence morality – is. The chapter shows that under the Christian surface the authors can see deep and pervasive influence of classical – particularly Aristotelian – ethics, and that this influence, properly understood, really does prompt us to re-evaluate their whole way of thinking about morality. It shows that the importance of James's distinction between interpreting the law 'according to the meaning' and not to 'the literal sense thereof' in the context of Measure for Measure when the author comes to discuss law.