Virtuous people make good choices in life. In order for us to practice virtue, we must (1) figure out what is the right thing to do (truth) and (2) do it (action). We believe that human beings have souls, and that it is movement in the soul which causes both thoughts and movements in the body. Now, there are three things in the soul that pertain to truth and action; they are sensation, reason, and desire. If we are going to be practicing virtue, then we must use these parts of the soul to do it. It stands to reason that the better these parts are at what they do, the better we will be able to practice virtue when we use them.

We have spoken at length about sensation in our work "On the Soul". Here we will set it aside, noting only that it does not further enter into our discussion of virtue. Sensation (1) is held also by the lower animals, but (2) it does not originate any action.

Now, when it comes to thinking, when we take something proposed under consideration, we can affirm it or negate it. Someone may propose to us that light meat is good. We may then enquire and find that (1) light meats are digestible, (2) digestible foods are healthy, and (3) healthy foods are good. When, therefore, we get to the end of our thinking, we affirm that light meats are, indeed, good. So likewise, in desire, we can pursue something (go after it and try to get it) or avoid it (keep away from it). Say we are hungry and our faculty of desire has us wish for and try to get some light meats for our lunch. In this case, when we pursue the light meats (viz. go to find and purchase them), it is very much like affirming that they are good. Contrariwise, if someone were to claim that sea water is good to drink, and we then reasoned that: (1) sea water is unhealthy, (2) unhealthy things are bad, and (3) sea water is bad to drink, then we will have negated the proposition. And if we are thirsty (viz. we have appetite) then we would still, with our faculty of desire, seek to avoid drinking sea water.

So, we can see that desire is important for virtue, because we cannot desire anything and everything that may satisfy our appetite, but rather we must desire what is right. (Notice here how this is similar to the mean being the right thing, in the right amount, at the right time.) And again, desire is not the same as appetite. One may have an appetite for food in general, a taste for sweet foods, and yet have no desire for them. This is possible because desire may be used with reason. We may initially desire something, and then when we learn something more about it, and reason about it, then we want it (i.e. desire it) no longer. We can take again our example of being very thirsty, and having our appetite moving us to drink sea water, but however, our desire is for our health, and we use it to resist the urge and avoid drinking. Desire and appetite may be, at times, at odds with one another, and so they do battle with one another.

Moral virtue is a state of character that is specifically about choice. Who you are is shown in what you choose in the different situations which come up in life. To be virtuous, we must choose for what is best. But just what is choice? Choice is desire plus reason. So, if we are to make good choices, then we must both have good reasoning (i.e. work out what really is so) and good desire (i.e. want what really is good). This means that desire should follow reason (and not appetite). If, by reasoning things out, we find that such-and-such a thing really is good, then we should desire it as being good.

Note here that we are talking about the practical intellect, specifically the part of the intellect that is about doing things. Generally speaking, the intellect is about thinking things over and ending up in a state of truth (i.e. getting things right), which is the good state, or falsity (i.e. getting things wrong), which is the bad state. For the practical intellect, the good state is, specifically, knowing what is good for oneself and wanting it.

Actions come from people choosing to do things. But people do not choose to do things for no reason. People choose to do things because they think that it would be good to have done the thing, and so, therefore, they want to do it. We cannot have choice without desire for something good (i.e. a moral state) and reasoning to help us figure out what really is good. In order for a person to be able to take actions (as opposed to just be moved by passions), and in order for those actions to be good or bad, a person must have both intellect and character.

And the intellect, by itself, is not enough. Thinking without wanting begets no action. In this way, the practical intellect is both like and unlike the productive intellect (which is concerned with making things): No one makes things for no reason, but, rather, they make in order to accomplish something. So likewise, people do not act for no reason, but for the sake of something (they think to be) good. However, unlike making, which is always for some specific end, people do act for the sake of action itself. A good person will always be looking to do another a good turn, just for the sake of that.

We can look at choice as either (a) reasoning which decides that some thing is good to have or (b) wanting to have some thing that it makes sense to have. Taken either way, we can see choice to be the thing which separates man from the lower animals; choice is what causes us to take action, while the lower animals are moved by passion alone.

(And on a side note, we do not choose things after the fact. No one chooses to sack the City of Troy, that is impossible since it has already been destroyed. No one deliberates about the past, but rather about the future, and what may or may not be, what is already past must be what it is. Agathon is right in saying:

There is only one thing which God himself cannot do --

Make undone what is done.)

The point of both the intellectual parts is to figure out what really is so. So, it stands to reason that the excellence of the parts will be whatever it is that makes them better at finding out the truth. And, by extension, being better at finding out that which really is so (i.e. the truth) should also make for being better at finding the mean, and thus also being better able to get virtue for oneself.