What education is, and how children ought to be instructed, is what should be well known; for there are doubts concerning the business of it, as all people do not agree in those things they would have a child taught, both with respect to their improvement in virtue and a happy life: nor is it clear whether the object of it should be to improve the reason or rectify the morals. From the present mode of education we cannot determine with certainty to which men incline, whether to instruct a child in what will be useful to him in life; or what tends to virtue, and what is excellent: for all these things have their separate defenders. As to virtue, there is no particular [1337b] in which they all agree: for as all do not equally esteem all virtues, it reasonably follows that they will not cultivate the same. It is evident that what is necessary ought to be taught to all: but that which is necessary for one is not necessary for all; for there ought to be a distinction between the employment of a freeman and a slave. The first of these should be taught everything useful which will not make those who know it mean. Every work is to be esteemed mean, and every art and every discipline which renders the body, the mind, or the understanding of freemen unfit for the habit and practice of virtue: for which reason all those arts which tend to deform the body are called mean, and all those employments which are exercised for gain; for they take off from the freedom of the mind and render it sordid. There are also some liberal arts which are not improper for freemen to apply to in a certain degree; but to endeavour to acquire a perfect skill in them is exposed to the faults I have just mentioned; for there is a great deal of difference in the reason for which any one does or learns anything: for it is not illiberal to engage in it for one's self, one's friend, or in the cause of virtue; while, at the same time, to do it for the sake of another may seem to be acting the part of a servant and a slave. The mode of instruction which now prevails seems to partake of both parts.