Nicomachean Ethics, Book II

Aristotle opens Book II by dividing virtue into two kinds: intellectual and moral.

Intellectual virtues are excellences of thought: things like wisdom, understanding, and practical judgment. These are acquired mostly through teaching. They take time, because thinking well about complex matters takes experience, but the basic method of acquiring them is instruction.

Moral virtues are excellences of character: things like courage, generosity, honesty, justice, temperance. These are not acquired through teaching. You cannot become courageous by listening to a lecture on courage. Moral virtues are acquired through habit.

This is a distinction worth lingering on. Aristotle is saying that there is a kind of knowledge you can get from a book (intellectual virtue) and a kind of knowledge you cannot (moral virtue). Moral knowledge lives in your habits, your reactions, your dispositions. You can read about generosity for a year, but that will not make you generous. What makes you generous is acting generously, over and over, until acting that way becomes second nature.

The Greek word Aristotle uses for this settled, habituated state of character is hexis. A hexis is not a feeling you happen to have; it is a stable disposition to feel, think, and act in certain ways. Virtues are hexeis.

Aristotle draws an analogy that is worth sitting with for a moment (and then doing something about). Nobody is born able to play the lyre. You become a good lyre player by playing the lyre, over and over, under the guidance of someone who already plays well. You learn by doing, and in particular, by doing the right thing repeatedly until doing it becomes automatic. The same, Aristotle says, goes for virtue.

"Men become builders by building," he writes, "and lyre players by playing the lyre; so too we become just by doing just acts, temperate by doing temperate acts, brave by doing brave acts."

This claim has a strange feature that is easy to miss. How do you do a just act before you are just? How do you do a brave act before you are brave? Aristotle acknowledges the puzzle. His answer is that there is a difference between doing the act that a virtuous person would do and doing it the way a virtuous person would do it. At first, you are doing the former. You perform the just act because someone told you to, or because you are imitating someone, or because you are figuring out what justice requires in this case. Over time, through repetition, something shifts. You begin to do the just act because it is just, not because you were told to, and you begin to take pleasure in doing it. That is when you have become just.

This is why Aristotle thinks moral education matters so much. The habits you form early are the habits you will have later. Children who are raised in households where honesty is practiced will find honesty natural as adults. Children raised around cruelty or indifference will not. There is nothing fatalistic here (adults can and do change), but it is harder to build a good character late than early, and Aristotle is clear-eyed about that.

Once you know what a virtue is (a stable disposition acquired by habituation), you can ask what distinguishes a virtuous disposition from a vicious one. Aristotle's answer is the doctrine of the mean.

The basic idea is this. Every virtue sits between two vices: a vice of excess and a vice of deficiency. The virtue is the mean between them. Aristotle is not talking about a mathematical average. He is talking about getting things right: the right response, at the right time, toward the right person, for the right reason.

Courage is the clearest example. Courage is the mean between cowardice and rashness. A coward feels too much fear; he runs from dangers he should face. A rash person feels too little fear; he charges into dangers he should avoid. The courageous person feels the fear that is appropriate to the situation and acts well in light of it. Courage is not the absence of fear; it is fear properly calibrated.

Consider more examples:

Two clarifications about the doctrine of the mean.

First, the mean is relative to the person and the situation. The right amount of food for a small person is not the right amount for a large person. The right level of assertiveness at your mother's funeral is not the right level at a business negotiation. Aristotle uses the example of Milo, a famous athlete, who needed far more food than an ordinary person. The mean is not a fixed quantity; it is getting it right, for this person, in this situation.

Second, not every action admits of a mean. Aristotle is explicit that some actions are just wrong, period. Murder, theft, adultery: there is no virtuous amount of these. You cannot commit the right amount of murder at the right time toward the right person. The doctrine of the mean applies to capacities and feelings that admit of degree: fear, anger, confidence, pleasure, appetite. Not everything morally significant is like that.

Here is where students often get frustrated with Aristotle. The doctrine of the mean sounds helpful in the abstract, but how do you actually find the mean in a particular case? How do you know when fear is properly calibrated, when generosity becomes wastefulness, when an honest remark becomes a cruel one?

Aristotle's answer will not satisfy everyone, but it is honest. There is no formula. There is no rule you can consult. The only thing that reliably identifies the mean is the judgment of a phronimos: a person of practical wisdom.

Practical wisdom (phronesis) is the intellectual virtue that allows a person to perceive what the situation calls for and act accordingly. A phronimos has enough experience of life, and has reflected enough on that experience, to see a moral situation clearly and respond well. When we want to know what courage requires here, now, in this case, we look at what a courageous person of good judgment would do.

This is sometimes mocked as circular: the virtuous action is what the virtuous person does, and the virtuous person is the one who does virtuous actions. But Aristotle is making a subtler point. He is saying that ethical knowledge is not the kind of knowledge that can be reduced to rules. You cannot write a book that will tell you what the right thing to do is in every situation. What you can do is cultivate the perceptual skill to see what situations call for, and that skill is developed through experience, reflection, and good company.

If this seems like a weakness of Aristotle's ethics, notice that every ethical theory runs into a version of it eventually. Kant will give us a rule (the categorical imperative), but applying the rule to particular cases requires judgment Kant does not fully explain. Mill will tell us to maximize happiness, but calculating consequences in real cases requires judgment Mill does not fully explain. Aristotle is the thinker who is most honest about this: ethical life is the life of a skilled perceiver, not a rule-follower.

Watch this lecture after you have read Book II and worked through the material above. Pay particular attention to the discussion of habituation and the doctrine of the mean.