Epicurus was not at all interested in what we would call the problems of mass society, and he thought civic politics was just trouble and to be avoided by the wise.

Moral theory develops from the divine command theory of medieval Christian philosophy, mixed up with a bit of ancient pagan virtue theory, to the purely secular moral sentiment and interpersonal reaction theories of Smith and Hume, to Kant's attempt to restore command theory but with something supersensible in the individual rather than God as the source of authority.

'Contract' succeeded 'status' as the basic organising principle in modern political vs. ancient society.

People's wants are not fixed; they generally want what others in their chosen comparison class appear to be enjoying and what advertising presents to them as attainable for them and as bringing happiness.

You can reasonably make the intellectual journey from thinking it's permissible to eat shrimp to thinking it's not permissible, or vice versa, whereas our slavery journey was uni-directional. We are as certain we are not going back to that old kind of slavery as we are that we aren't going back to the geocentric universe.

Atomism had no absolute 'above' and 'below' and no such rulers, so favoured the undersranding of justice as an agreement amongst equals.

Claims like 'Slavery is wrong' are not fully common-sensical, so they must be at least partly theoretical.