Evolution of 'Supererogation'
It is advisable to get into a discussion about this question only after one knows what ‘supererogation’ means and how it has been discussed for centuries. In the Greek ethics (especially as Aristotle formulated it), the notion plays a very crucial role without it being related to a normative sense of duty. With the Catholics, especially as Aquinas gave expression to it, a normative notion of duty …