Since happiness is an activity of the soul in conformity with perfect virtue, it is now necessary to determine the nature of this virtue or excellence. This will make it possible for us to determine more clearly the nature of goodness in regard to both ethics and politics, a matter of great attention to the statesman, who devotes his most serious attention to his efforts to make good men of his fellow citizens.
Needless to say, the virtue we must consider is human virtue, for we are seeking after the nature of human good and human happiness. By human virtue we mean an excellence of the soul, not the body, for happiness has been defined as an activity of the soul. Clearly then, it is necessary for a statesman to have some knowledge of the workings of the soul, or psychology. We will limit this inquiry to the extent required for the proper study of ethics.
Some of the doctrines on the soul stated in our earlier, less technical works on the subject, are adequate for our present purposes. Let us review them:
- The soul consists of two elements, one rational and the other irrational. Whether these are physically separate, or are separate only abstractly (e.g., as are the concave and convex portions of a lens) is irrelevant to our present purpose.
- The irrational element of the soul is divided into two parts. The first is vegetative in nature and common to all living things, thus it is not relevant to a discussion of human virtue. The other part is the source from which all appetites and desires spring (i.e., the emotions). This part, though irrational, bears a special relation to the rational faculties in that it can be made submissive to the reason and obedient to its dictates.
These distinctions within the soul allow us to make a classification of the virtues, analogous to the classification of the parts of the soul. Some virtues are called "intellectual" (e.g., wisdom, intelligence, prudence) and are virtues of the rational faculty of the soul. Other virtues, like generosity or liberality and temperance or self-control are "moral" virtues, the virtues of character, and belong to the irrational element of the soul. They are attained when the irrational element is made to act in accordance with the dictates of the reason. Because it can be made subject to the reason, this element of the soul may actually be classified as intermediate, not fully rational or irrational, but this is not of great importance at this point.
Most ancient Greek thought about the nature of human life was governed by two fundamental assumptions and these are the basis of Aristotle's approach to the study of ethics:
- That human life is comprehensible only when conceived of as being directed toward some end or good, and that it can be interpreted by a categorization of ends and means. In the sense that human life is thought to contain an ideal element, most Greek moral philosophy, including Aristotle's, is idealistic. Since Aristotle's moral system is concerned with determining ultimate causes and ends it can also be considered teleological.
- That the end toward which all practical human activity is directed is definable in advance of its realization. This takes moral knowledge out of the realm of abstraction and speculation, and gives it great practical importance as a code for personal life and a guide for the organization and administration of the political state.