There is a famous question discussed in one of the earlier Dialogues of Plato (Protagoras, 329, 330; cp. Arist. Nic. Ethics, vi. 13. 6), 'Whether the virtues are one or many?' This receives an answer which is to the effect that there are four cardinal virtues { lxiv} (now for the first time brought together in ethical philosophy), and one supreme over the rest, which is not like Aristotle's conception of universal justice, virtue relative to others, but the whole of virtue relative to the parts. To this universal conception of justice or order in the first education and in the moral nature of man, the still more universal conception of the good in the second education and in the sphere of speculative knowledge seems to succeed. Both might be equally described by the terms 'law,' 'order,' 'harmony;' but while the idea of good embraces 'all time and all existence,' the conception of justice is not extended beyond man.
... Socrates is now going to identify the individual and the State. But first he must prove that there are three parts of the individual soul. His argument is as follows:--Quantity makes no difference in quality. The word 'just,' whether applied to the individual or to the State, has the same meaning. And the term 'justice' implied that the same three principles in the State and in the individual were doing their own business. But are they really three or one? The question is difficult, and one which can hardly be solved by the methods which we are now using; but the truer and longer way would take up too much of our time. 'The shorter will satisfy me.' Well then, you would admit that the qualities of states mean the qualities of the individuals who compose them? The Scythians and Thracians are passionate, our own race intellectual, *436* and the Egyptians and Phoenicians covetous, because the individual members of each have such and such a character; the difficulty is to determine whether the several principles are one or three; whether, that is to say, we reason with one part of our nature, desire with another, are angry with another, or whether the whole soul comes into play in each sort of action. This enquiry, however, requires a very exact definition of terms. The same thing in the same relation cannot be affected in two opposite ways. But there is no impossibility in a man standing still, yet moving his arms, or in a top which is fixed on one spot going round upon its axis. There is no necessity to mention all the possible exceptions; *437* let us provisionally assume that opposites cannot do or be or suffer opposites in the same relation. And to the class of opposites belong assent and dissent, desire and avoidance. And one form { lxv} of desire is thirst and hunger: and here arises a new point--thirst is thirst of drink, hunger is hunger of food; not of warm drink or of a particular kind of food, *438* with the single exception of course that the very fact of our desiring anything implies that it is good. When relative terms have no attributes, their correlatives have no attributes; when they have attributes, their correlatives also have them. For example, the term 'greater' is simply relative to 'less,' and knowledge refers to a subject of knowledge. But on the other hand, a particular knowledge is of a particular subject. Again, every science has a distinct character, which is defined by an object; medicine, for example, is the science of health, although not to be confounded with health. *439* Having cleared our ideas thus far, let us return to the original instance of thirst, which has a definite object--drink. Now the thirsty soul may feel two distinct impulses; the animal one saying 'Drink;' the rational one, which says 'Do not drink.' The two impulses are contradictory; and therefore we may assume that they spring from distinct principles in the soul. But is passion a third principle, or akin to desire? There is a story of a certain Leontius which throws some light on this question. He was coming up from the Piraeus outside the north wall, and he passed a spot where there were dead bodies lying by the executioner.