But when they consider they must always live together, they must needs love one another, and in this way they really learn to love one another. The pupil is not ashamed to follow as a child the friend who will be with him in manhood; the tutor takes an interest in the efforts whose fruits he will enjoy, and the virtues he is cultivating in his pupil form a store laid up for his old age. This agreement made beforehand assumes a normal birth, a strong, well-made, healthy child. A father has no choice, and should have no preference within the limits of the family God has given him; all his children are his alike, the same care and affection is due to all. Crippled or well-made, weak or strong, each of them is a trust for which he is responsible to the Giver, and nature is a party to the marriage contract along with husband and wife. But if you undertake a duty not imposed upon you by nature, you must secure beforehand the means for its fulfilment, unless you would undertake duties you cannot fulfil. If you take the care of a sickly, unhealthy child, you are a sick nurse, not a tutor. To preserve a useless life you are wasting the time which should be spent in increasing its value, you risk the sight of a despairing mother reproaching you for the death of her child, who ought to have died long ago. I would not undertake the care of a feeble, sickly child, should he live to four score years. I want no pupil who is useless alike to himself and others, one whose sole business is to keep himself alive, one whose body is always a hindrance to the training of his mind. If I vainly lavish my care upon him, what can I do but double the loss to society by robbing it of two men, instead of one? Let another tend this weakling for me; I am quite willing, I approve his charity, but I myself have no gift for such a task; I could never teach the art of living to one who needs all his strength to keep himself alive. The body must be strong enough to obey the mind; a good servant must be strong. I know that intemperance stimulates the passions; in course of time it also destroys the body; fasting and penance often produce the same results in an opposite way. The weaker the body, the more imperious its demands; the stronger it is, the better it obeys. All sensual passions find their home in effeminate bodies; the less satisfaction they can get the keener their sting. A feeble body makes a feeble mind. Hence the influence of physic, an art which does more harm to man than all the evils it professes to cure. I do not know what the doctors cure us of, but I know this: they infect us with very deadly diseases, cowardice, timidity, credulity, the fear of death. What matter if they make the dead walk, we have no need of corpses; they fail to give us men, and it is men we need.