. . . the philosophic science which establishes the right or moral order of human acts, that is, in the light of first principles, ethics determines the absolutely necessary norms of free acts whose realization in practice makes us men.
Ethics is a philosophic science because it treats of the ultimate principles of conduct. To be a part of philosophy, or even a science at all, ethics must rest on metaphysics, the science of being in general. Since ethics explains the ultimate principles of conduct, in can criticize as morally right or wrong pronouncements of law, sociology, anthropology, economics, and the political sciences.
Ethics is philosophy for the reason that it bases its conclusions on UNAIDED REASON. For all of these reasons, ethics is commonly known as the science which studies what ought to be.
Inscribed on the portals of the temple at Delphi were the words of Apollo: "Know Thyself." And it was at Delphi, as the Apology tells us, that Socrates' mission began. Before Socrates, the significance of the Delphic injunction had been primarily understood as social: "Know Thyself" meant, "Know thy station and its duties, and do no tusurp a position not thine by right."
Socrates transformed the meaning of the injunction by turning it inward. The true aim of life, as he puts it in the Apology, is to "make one's one soul as good as possible"; human happiness consists in spiritual perfection, and spiritual perfection implies and is implied by self-knowledge. The claim of morality on a man is ultimately the claim of his own human nature on itself; only when a man has come clearly to understand himself, has come to know who he is and what he is, can he truly know good from evil. It is for this reason that "the unexamined life is not worth living," and it is this knowledge, rather than knowledge of natural causes, which deserves the name of Wisdom.
As a moral teacher, Socrates was peculiar in that he did not preach, but questioned, wearing all the while a mask of ironic ignorance. All of us, in moral matters, think we know what we do not know. The first aim of Socrates' questioning was to disperse this false conceit of knowledge. Socratic dialectic begins with refutation. Ask a man to tell you the meaning of some simple term, a term like courage, or justice; then question him about his definition and test it to see if it holds water. If it does not, bring him to see for himself the weakness of his vision. When the ground has thus been cleared, you can both enlist together in the common cause of finding out what is really the case, in a cooperative effort to discover the truth. What has been gained in this process by the respondent cannot be taken from him; he will come to see for himself, with the full clarity of immeditate insight, the nature of the virtue which before he had only dimly understood. It is because each man must see the truth for himself that virtue cannot be taught. You can teach a man what has usually been thought about virtue, for that is a fact, and facts may be learned by rote. But in order to understand virtue, one must apprehend it as directly and immediately as a theorem in geometry; and that apprehension cannot fail to reorder life. It was for this reason that Socrates identified knowledge with goodness in his paradoxical statement, "virtue is knowledge." It would be more accurate to say, perhaps, that virtue is self-knowledge, knowledge of the nature of one's own soul, of the true end of life and the means to attain it.
1 - The Free Press. New York: 1991