XII. MENTAL CAUSES OF DISEASE.--A man may give too much attention to his health and the means for its preservation, and the doing so is both a sign and a cause of disease--probably oftener the former than the latter, except in cases of psychological epidemics. The power of expectant attention, especially if accompanied by belief or fear, to produce derangement of function in the nervous system, and through this to affect the circulatory and digestive systems, is well known to medical men. The effects of an undue amount of brain-work, and especially of the anxiety and worry which often accompany this when it is specially directed to the acquiring of wealth, fame, or power, are also familiar to physicians in our large cities. The analogies between mental and physical exertion are close in some respects, and especially as to the effects of over-exertion in a limited time under the influence of excitement. The danger from simple mental work, such as study, when there is no excitement from a contest, is small, and depends mainly on lack of physical exercise and consequent disorder of the digestive organs. The risk of producing what Fothergill calls "physiological bankruptcy" is greatest in the youth studying for a prize, the speculator, the man who feels responsibility which he knows he probably cannot meet. The danger of injury from overwork under excitement is a very real one in many of our schools, and, while the evil results are most apparent in girls of the middle and upper classes, the boys and the young men also suffer. The system of pass examinations, in which the standing of the pupil is to be determined, not from the average results of his daily recitations, but from a single examination at the end of the year, produces the greatest risks to health; and this is especially the case where the ambition and pride of the children are stimulated by competition for prizes, medals, etc. Such systems of grading by a single final examination should not be used in ordinary schools, and for some pupils there will always be a risk to health connected with them even when they are of age. No doubt the stimulus of {205} competition is useful with the majority of children as well as of adults, but with some of them it is pretty sure to go too far. The symptoms produced by undue mental strain are familiar to all physicians, and there is usually little difficulty in tracing the effect to the cause when attention has been directed to the matter; in fact, the patient himself usually knows very well the cause of his troubles. The remedy is, of course, rest--but that does not mean idleness. In speaking of occupation, allusion has been made to the fact that the physician must at times advise his patient as to the adoption of some pursuit, and in cases of this kind such advice is also useful.