Virtue being, as we have seen, of two kinds, intellectual and moral, intellectual virtue is for the most part both produced and increased by instruction, and therefore requires experience and time; whereas moral or ethical virtue is the product of habit (ethos), and has indeed derived its name, with a slight variation of form, from that word.¹ And therefore it is clear that none of the moral virtues formed is engendered in us by nature, for no natural property can be altered by habit. For instance, it is the nature of a stone to move downwards, and it cannot be trained to move upwards, even though you should try to train it to do so by throwing it up into the air ten thousand times; nor can fire be trained to move downwards, nor can anything else that naturally behaves in one way be trained into a habit of behaving in another way. The virtues² therefore are engendered in us neither by nature nor yet in violation of nature; nature gives us the capacity to receive them, and this capacity is brought to maturity by habit. Moreover, the faculties given us by nature are bestowed on us first in a potential form; we exhibit their actual exercise afterwards. This is clearly so with our senses: we did not acquire the faculty of sight or hearing by repeatedly seeing or repeatedly listening, but the other way about—because we had the senses we began to use them, we did not get them by using them. The virtues on the other hand we acquire by first having actually practised them, just as we do the arts. We learn an art or craft by doing the things that we shall have to do when we have learnt it³: for instance, men become builders by building houses, harpers by playing on the harp. 1103bSimilarly we become just by doing just acts, temperate by doing temperate acts, brave by doing brave acts. This truth is attested by the experience of states: lawgivers make the citizens good by training them in habits of right action—this is the aim of all legislation, and if it fails to do this it is a failure; this is what distinguishes a good form of constitution from a bad one. Again, the actions from or through which any virtue is produced are the same as those through which it also is destroyed—just as is the case with skill in the arts, for both the good harpers and the bad ones are produced by harping, and similarly with builders and all the other craftsmen: as you will become a good builder from building well, so you will become a bad one from building badly. Were this not so, there would be no need for teachers of the arts, but everybody would be born a good or bad craftsman as the case might be. The same then is true of the virtues. It is by taking part in transactions with our fellow-men that some of us become just and others unjust; by acting in dangerous situations and forming a habit of fear or of confidence we become courageous or cowardly. And the same holds good of our dispositions with regard to the appetites, and anger; some men become temperate and gentle, others profligate and irascible, by actually comporting themselves in one way or the other in relation to those passions. In a word, our moral dispositions are formed as a result of the corresponding activities. Hence it is incumbent on us to control the character of our activities, since on the quality of these depends the quality of our dispositions. It is therefore not of small moment whether we are trained from childhood in one set of habits or another; on the contrary it is of very great, or rather of supreme, importance.

As then our present study, unlike the other branches of philosophy, has a practical aim (for we are not investigating the nature of virtue for the sake of knowing what it is, but in order that we may become good, without which result our investigation would be of no use), we have consequently to carry our enquiry into the region of conduct, and to ask how we are to act rightly; since our actions, as we have said, determine the quality of our dispositions. Now the formula “to act in conformity with right principle” is common ground, and may be assumed as the basis of our discussion. (We shall speak about this formula later,⁴ and consider both the definition of right principle and its relation to the other virtues.) 1104aBut let it be granted to begin with that the whole theory of conduct is bound to be an outline only and not an exact system, in accordance with the rule we laid down at the beginning,⁵ that philosophical theories must only be required to correspond to their subject matter; and matters of conduct and expediency have nothing fixed or invariable about them, any more than have matters of health. And if this is true of the general theory of ethics, still less is exact precision possible in dealing with particular cases of conduct; for these come under no science or professional tradition, but the agents themselves have to consider what is suited to the circumstances on each occasion, just as is the case with the art of medicine or of navigation. But although the discussion now proceeding is thus necessarily inexact, we must do our best to help it out. First of all then we have to observe, that moral qualities are so constituted as to be destroyed by excess and by deficiency—as we see is the case with bodily strength and health (for one is forced to explain what is invisible by means of visible illustrations). Strength is destroyed both by excessive and by deficient exercises, and similarly health is destroyed both by too much and by too little food and drink; while they are produced, increased and preserved by suitable quantities. The same therefore is true of Temperance, Courage, and the other virtues. The man who runs away from everything in fear and never endures anything becomes a coward; the man who fears nothing whatsoever but encounters everything becomes rash. Similarly he that indulges in every pleasure and refrains from none turns out a profligate, and he that shuns all pleasure, as boorish persons do, becomes what may be called insensible. Thus Temperance and Courage are destroyed by excess and deficiency, and preserved by the observance of the mean. But⁶ not only are the virtues both generated and fostered on the one hand, and destroyed on the other, from and by the same actions, but they will also find their full exercise in the same actions. This is clearly the case with the other more visible qualities, such as bodily strength: for strength is produced by taking much food and undergoing much exertion, while also it is the strong man who will be able to eat most food and endure most exertion. The same holds good with the virtues. We become temperate by abstaining from pleasures, and at the same time we are best able to abstain from pleasures when we have become temperate. 1104bAnd so with Courage: we become brave by training ourselves to despise and endure terrors, and we shall be best able to endure terrors when we have become brave.

An index of our dispositions is afforded by the pleasure or pain that accompanies our actions. A man is temperate if he abstains from bodily pleasures and finds this abstinence itself enjoyable, profligate if he feels it irksome; he is brave if he faces danger with pleasure or at all events without pain, cowardly if he does so with pain. In fact pleasures and pains are the things with which moral virtue is concerned. For (1) pleasure causes us to do base actions and pain cause us to abstain from doing noble actions. Hence the importance, as Plato points out, of having been definitely trained from childhood to like and dislike the proper things; this is what good education means. (2)Again, if the virtues have to do with actions and feelings, and every action is attended with pleasure or pain, this too shows that virtue has to do with pleasure and pain. (3) Another indication is the fact that pain is the medium of punishment; for punishment is a sort of medicine, and the nature of medicine to work by means of opposites.⁷ (4)Again, as we said before, every formed disposition of the soul realizes its full nature⁸ in relation to and in dealing with that class of objects by which it is its nature to be corrupted or improved. But men are corrupted through pleasures and pains, that is, either by pursuing and avoiding the wrong pleasures and pains, or by pursuing and avoiding them at the wrong time, or in the wrong manner, or in one of the other wrong ways under which errors of conduct can be logically classified. This is why some thinkers⁹ define the virtues as states of impassivity or tranquillity, though they make a mistake in using these terms absolutely, without adding “in the right (or wrong) manner” and “at the right (or wrong) time” and the other qualifications. We assume therefore that moral virtue is the quality of acting in the best way in relation to pleasures and pains, and that vice is the opposite. But the following considerations also will give us further light on the same point. (5) There are three things that are the motives of choice and three that are the motives of avoidance; namely, the noble, the expedient, and the pleasant, and their opposites, the base, the harmful, and the painful. Now in respect of all these the good man is likely to go right and the bad to go wrong, but especially in respect of pleasure; for pleasure is common to man with the lower animals, and also it is a concomitant of all the objects of choice, 1105asince both the noble and the expedient appear to us pleasant. (6) Again, the susceptibility to pleasure has grown up with all of us from the cradle. Hence this feeling is hard to eradicate, being engrained in the fabric of our lives. (7) Again, pleasure and pain are also¹⁰ the standards by which we all, in a greater or less degree, regulate our actions. On this account therefore pleasure and pain are necessarily our main concern, since to feel pleasure and pain rightly or wrongly has a great effect on conduct. (8) And again, it is harder to fight against pleasure than against anger (hard as that is, as Heracleitus¹¹ says); but virtue, like art, is constantly dealing with what is harder, since the harder the task the better is success. For this reason also therefore pleasure and pain are necessarily the main concern both of virtue and of political science, since he who comports himself towards them rightly will be good, and he who does so wrongly, bad. We may then take it as established that virtue has to do with pleasures and pains, that the actions which produce it are those which increase it, and also, if differently performed, destroy it, and that the actions from which it was produced are also those in which it is exercised.