The ancients apparently took it as a given that individuals are not, in general, authorities about their own welfare. ... The standard economic view of modernity - that well-being consists roughly in people getting whatever they happen to want - would have seemed childish if not insane to most ancient thinkers.
I find myself halfway between the ancients and the moderns on this one.
On the one hand, I do think human beings, as a group, are designed to flourish by living a distinctive way. This way is broadly defined and forgiving of missteps. It is not, though, simply whatever anyone happens to want. If we live the good life, we will flourish. If we do not, we will have a worse time, in the way that trying to run a car without oil means the car will not run well.
On the other hand, I don't see any psychological process that could make people live as they were designed to if they don't want to. And I don't see any just social structure that should try to constrain people so much that they could only live one way.
I think the great benefit of a free society is not that everyone is free to do what he or she wants. I think the great benefit of a free society is that those who want to flourish by living virtuously are free to do so, amidst other ways of living.