5. Ethics
(a) The Ethics of the Individual
Just as Plato's theory of knowledge begins with a negative portion, designed to refute false theories of what truth is, so does his theory of morals begin with a negative portion, intended to refute false theories of what virtue is. These two negative departments of Plato's philosophy correspond in every way. As he was then engaged in showing that knowledge is not perception, as Protagoras thought, so he now urges that [{218}] virtue is not the same as pleasure. And as knowledge is not mere right opinion, neither is virtue mere right action. The propositions that knowledge is perception, and that virtue is pleasure, are indeed only the same principle applied to different spheres of thought. For the Sophists whatever appeared true to the individual was true for that individual. This is the same as saying that knowledge is perception. For the Sophists, again, whatever appeared right to the individual was right for that individual. This is the same as saying that it is right for each man to do whatever he pleases. Virtue is defined as the pleasure of the individual. This consequence of the Sophistic principles was drawn both by many of the Sophists themselves, and later by the Cyrenaics.
As these two propositions are thus in fact only one principle, what Plato has said in refutation of the former provides also his refutation of the latter. The theory that virtue is pleasure has the same destructive influence upon morals as the theory that knowledge is perception had upon truth. We may thus shortly summarize Plato's arguments.
(1) As the Sophistic theory of truth destroys the objectivity of truth, so the doctrine that virtue is the pleasure of the individual destroys the objectivity of the good. Nothing is good in itself. Things are only good for me or for you. There results an absolute moral relativity, in which the idea of an objective standard of goodness totally disappears.
(2) This theory destroys the distinction between good and evil. Since the good is whatever the individual pleases, and since the pleasure of one individual is the [{219}] displeasure of another, the same thing is both good and evil at the same time, good for one person and evil for another. Good and evil are therefore not distinct. They are the same.
(3) Pleasure is the satisfaction of our desires. Desires are merely feelings. This theory, therefore, founds morality upon feeling. But an objective morality cannot be founded upon what is peculiar to individuals. If the moral code is to be a law binding upon all men, it can only be founded upon that which is common to all men, the universal reason.
(4) The end of moral activity must fall within, and not outside, the moral act itself. Morality must have an intrinsic, not a merely extrinsic, value. We must not do right for the sake of something else. We must do right because it is right, and thus make virtue an end in itself. But the Sophistic theory places the end of morality outside morality. We are to do right, not for its own sake, but for the sake of pleasure. Morality is thus not an end in itself, but merely a means towards a further end.
Virtue, therefore, is not pleasure, any more than knowledge is perception. Likewise, just as knowledge is not right opinion, so virtue is not right action. Right opinion may be held upon wrong grounds, and right action may be performed on wrong grounds. For true virtue we must not only know what is right, but why it is right. True virtue is thus right action proceeding from a rational comprehension of true values. Hence there arises in Plato's philosophy a distinction between philosophic virtue and customary virtue. Philosophic virtue is founded upon reason, and understands the [{220}] principle on which it acts. It is, in fact, action governed by principles. Customary virtue is right action proceeding from any other grounds, such as custom, habit, tradition, good impulses, benevolent feelings, instinctive goodness. Men do right merely because other people do it, because it is customary, and they do it without understanding the reasons for it. This is the virtue of the ordinary honest citizen, the "respectable" person. It is the virtue of bees and ants, who act as if rationally, but without any understanding of what they are doing. And Plato observes--no doubt with an intentional spice of humour--that such people may in the next life find themselves born as bees and ants. Plato denies philosophic virtue not only to the masses of men, but even to the best statesmen and politicians of Greece.
As true virtue is virtue which knows at what it is aiming, the knowledge of the nature of the highest aim becomes the chief question of ethics. What is the end of moral activity? Now we have just seen that that end must fall within, and not outside, the moral act. The end of goodness is the good. What, then, is the good? What is the supreme good, the summum bonum?