From the commandment "Preserve thy life" it follows not only that we should not lay violent hands upon ourselves, but that we should do all in our power to develop and invigorate the body, in order that it may become an efficient instrument in the service of our higher aims. The teacher should inform himself on the subject of the gymnastic ideal of the Greeks and consider in how far this ideal is applicable to modern conditions. In general, the teacher should explore as fully as possible the ethical problems on which he touches. He should not be merely "one lesson ahead" of his pupils. Really it is necessary to grasp the whole of a subject before we can properly set forth its elements. A very thorough normal training is indispensable to those who would give moral instruction to the young. The duties of cleanliness and temperance fall under the same head as the above. In speaking of cleanliness, there are three motives--the egoistic, the aesthetic, and the moral--to which we may appeal. Be scrupulously clean for the sake of health, be clean lest you become an object of disgust to others, be clean in order to retain your self-respect. Special emphasis should be laid on secret cleanliness. Indolent children are sometimes neat in externals, but shockingly careless in what is concealed from view. The motive of self-respect shows itself particularly in secret cleanliness. The duty of temperance is supported by the same three motives. Intemperance undermines health, the glutton or the drunkard awakens disgust, intemperance destroys self-respect. To strengthen the repugnance of the pupils against intemperance in eating, contrast the way in which wild beasts eat with that in which human beings partake of their food. The beast is absorbed in the gratification of its appetite, eats without the use of implements, eats unsocially. The human way of eating is in each particular the opposite. Show especially that the act of eating is spiritualized by being made subservient to friendly intercourse and to the strengthening of the ties of domestic affection. The family table becomes the family altar. Call attention also to the effects of drunkenness; point out the injuries which the drunkard inflicts on wife and children by his neglect to provide for them, by the outbursts of violence to which he is subject under the influence of strong drink; describe his physical, mental, and moral degradation; lay stress on the fact that liquor deprives him of the use of his reason. With respect to temperance in food, there are one or two points to be noted. I say to my pupils if you are particularly fond of a certain dish, sweetmeats, for instance, make it a rule to partake less of that than if you were not so fond of it. This is good practice in self-restraint. I make out as strong a case as possible against the indulgence of the candy habit. Young people are not, as a rule, tempted to indulge in strong drink; but they are tempted to waste their money