The Ancient Greeks believed that all living things have soul. “Soul” had little or no religious significance back then; it just came with life, all life. Ants and birds, as well as humans, had it, at least as long as they were alive. It is true, however, that souls differed. Human soul was unique because it could reason. Remember, reason was our ergon, our defining human characteristic. Cats and cattle can feed themselves, move around, and they can see and hear; they have life and they have soul but they cannot think. We alone understand that “All men are mortal, Socrates is a man, therefore, Socrates is mortal.” Because of our ability to reason we are a little closer to the divine.

But we are far from perfect. We also have a powerful irrational side. The appetitive part of our soul that houses desires and emotions is often less than reasonable. Fortunately, and this is very important, the irrational side of us is able to listen to reason and take its advice. The irrational in us can be influenced by the rational. Aristotle's moral virtue is just that: irrational desires, emotions, and actions coming under the influence of reason.