MY programme is as follows: I shall draw a general distinction between morals and moral philosophy in order to show that an ethical theory cannot be neutral and autonomous but must have an empirical foundation. Both ethical naturalists and existentialists agree that an adequate moral theory must be based on anthropological considerations. They however differ on one major issue: ethical naturalists maintain that such a theory must be scientifically grounded, existentialists that it must be grounded on experience phenomenologically described. The (...) weakness of the naturalists’ position becomes apparent when some anthropological notion like the concept of action is clarified, since human behaviour of a morally relevant kind cannot be fully understood from a scientific point of view. (shrink)