in their respective cities; all of them shape the characters of their respective citizens, by enforcing habitual practice.  Some do it well; others ill; according to the practice, so will be the resulting character; as he that is practised in building badly, will be a bad builder in the end; and he that begins on a bad habit of playing the harp, becomes confirmed into a bad player.  Hence the importance of making the young perform good actions habitually and from the beginning.  The permanent ethical acquirements are generated by uniform and persistent practice (I.). [This is the earliest statement of the philosophy of habit.]

Everything thus turns upon practice:  and Aristotle reminds us that his purpose here is, not simply to teach what virtue is, but to produce virtuous agents.  How are we to know what the practice should be?  It must be conformable to right reason:  every one admits this, and we shall explain it further in a future book.  But let us proclaim at once, that in regard to moral action, as in regard to health, no exact rules can be laid down.  Amidst perpetual variability, each agent must in the last resort be guided by the circumstances of the case.  Still, however, something may be done to help him.  Here Aristotle proceeds to introduce the famous doctrine of the MEAN.  We may err, as regards health, both by too much and by too little of exercise, food, or drink.  The same holds good in regard to temperance, courage, and the other excellences (II.).

His next remark is another of his characteristic doctrines, that the test of a formed habit of virtue, is to feel no pain; he that feels pain in brave acts is a coward.  Whence he proceeds to illustrate the position, that moral virtue [Greek:  aethikae aretae] has to do with pleasures and pains.  A virtuous education consists in making us feel pleasure and pain at proper objects, and on proper occasions.  Punishment is a discipline of pain.  Some philosophers (the Cynics) have been led by this consideration to make virtue consist in apathy, or insensibility; but Aristotle would regulate, and not extirpate our sensibilities (III.).

But does it not seem a paradox to say (according to the doctrine of habit in I.), that a man becomes just, by performing just actions; since, if he performs just actions, he is already just?  The answer is given by a distinction drawn in a comparison with the training in the common arts of life.  That a man is a good writer or musician, we see by his writing or his music; we take no account of the state of his mind in other respects:  if he knows how to do this, it is enough.  But in respect to moral excellence, such knowledge is not enough:  a man may do just or temperate acts, but he is not necessarily a just or temperate man, unless he does them with right intention and on their own account.  This state of the internal mind, which is requisite to constitute the just and temperate man, follows upon the habitual practice of just and temperate acts, and follows upon nothing else.  But most men are content to talk without any such practice.  They fancy erroneously that knowing, without doing, will make a good man. [We have here the reaction against the Sokratic doctrine of virtue, and also the statement of the necessity of a prosper motive, in order to virtue.]