Full Idea
The advantage of modern thinkers over the ancient virtue ethicists is that in addition to imperfect duties (i.e. virtues) they also recognise the existence of perfect duties, or duties of justice, which are essential for the existence of society.
Gist of Idea
The ancients recognised imperfect duties, but we have added perfect duties like justice
Source
Daniel Statman (Introduction to Virtue Ethics [1997], §7)
Book Reference
'Virtue Ethics', ed/tr. Statman,Daniel [Edinburgh 1997], p.27
A Reaction
Even the Greeks had laws (e.g. Idea 422), so they understood that a society needs rules, but many laws don't seem to be moral rules (e.g. car parking), and the Greeks thought morality was about human excellence, not avoiding traffic jams.
Related Idea
Idea 422 The people should fight for the law as if for their city-wall [Heraclitus]