The virtue of a faculty is related to the special function which that faculty performs. Now there are three elements in the soul which control action and the attainment of truth: namely, Sensation, Intellect, and Desire. Of these, Sensation never originates action, as is shown by the fact that animals have sensation but are not capable of action.
Each man, if he attempts to join himself to others, is on all sides cramped and diminished of his proportion; and the stricter theunion, the smaller and the more pitiful he is. But leave him alone, to recognize in every hour and place the secret soul, he will go up and down doing the works of a true member, and, to the astonishment of all, the work will be done with concert, though no man spoke.
The attainment of truth is then the function of both the intellectual parts of the soul. Therefore their respective virtues are those dispositions which will best qualify them to attain truth.
So, if we must give a general formula applicable to all kinds of soul, we must describe it as the first actuality [entelechy] of anatural organized body.
Greatness of Soul seems therefore to be as it were a crowning ornament of the virtues; it enhances their greatness, and it cannot exist without them. Hence it is hard to be truly great-souled, for greatness of soul is impossible without moral nobility.