But if we should avoid negative ideas for our own sakes, much more should we do so for the sake of other people. Gloomy and despondent men and women are centres of mental contagion, damaging all with whom they come in contact. Sometimes such people seem involuntarily to exert themselves to quench the cheerfulness of brighter natures, as if their Unconscious strove to reduce all others to its own low level. But even healthy, well-intentioned people scatter evil suggestions broadcast, without the least suspicion of the harm they do. Every time we remark to an acquaintance that he is looking ill, we actually damage his health; the effect may be extremely slight, but by repetition it grows powerful. A man who accepts in the course of a day fifteen or twenty suggestions that he is ill, has gone a considerable part of the way towards actual illness. Similarly, when we thoughtlessly commiserate with a friend on the difficulty of his daily work, or represent it as irksome and uncongenial, we make it a little harder for him to accomplish, and thereby slightly diminish his chances of success. If we must supervise our speech in contact with adults, with children we should exercise still greater foresight. The child's Unconscious is far more accessible than that of the adult; the selective power exercised by the conscious mind is much feebler, and consequently the impressions received realise themselves with greater power. These impressions are the material from which the child's growing life is constructed, and if we supply faulty material the resultant structure will be unstable. Yet the most attentive and well-meaning mothers are engaged daily in sowing the seeds of weakness in their children's minds. The little ones are constantly told they will take cold, will be sick, will fall down, or will suffer some other misfortune. The more delicate the child's health, the more likely it is to be subjected to adverse suggestions. It is too often saturated with the idea of bad health, and comes to look on disease as the normal state of existence and health as exceptional. The same is equally true of the child's mental and moral upbringing. How often do foolish parents tell their children that they are naughty, disobedient, stupid, idle or vicious? If these suggestions were accepted, which, thank Heaven, is not always the case, the little ones would in very fact develop just these qualities. But even when no word is spoken, a look or a gesture can initiate an undesirable autosuggestion. The same child, visited by two strangers, will immediately make friends with the one and avoid the other. Why is this?--Because the one carries with him a healthful atmosphere, while the other sends out waves of irritability or gloom. "Men imagine," says Emerson, "that they communicate their virtue or vice only by overt actions, and do not see that virtue and vice emit a breath every moment."