I think it is clear that what we ought to do has to be independent of our decisions about what to do, and independent of any procedures we might use in making such decisions.

Kant does represents a distinctively modern view of the human condition in contrast to that of ancient high culture, found in ancient Greek ethics and also in ancient Chinese ethics.

I think that both Mill and Sidgwick are great and admirable philosophers, from whom we still have a lot to learn. I would not favor a form of Kantianism (if there is such a form) that treats Mill's or Sidgwick's moral philosophy with disrespect.

I think the term "Kantian constructivism" as an oxymoron. Kant was a constructivist about mathematics, but not about ethics.

When Marx, in the Theses on Feuerbach, says that only idealism up to now has understood the active side of material Praxis, what he says is more true of Fichte than of any other philosopher in the classical German tradition.

Utilitarians are usually empiricists who think they can solve every problem by accumulating enough empirical facts. They do not realize that thinking as well as experience is necessary to know anything or get anything right.

Not only in order to act morally, but even to formulate theoretical questions, devise experiments, choose which ones to perform and what conclusions to draw from then - we must presuppose that we are free. That's the sense in which it is true that for Kant "we must assume we are free."