If these views, in relation to the principal condition of insanity, are correct, it is evident that the question of largest interest in relation to its _prevention_, relates, not so much to the long catalogue of exciting or secondary causes, as to the avoidance of such courses of life, habits, and tendencies of society, as specially assist to develop and perpetuate this diathesis. It now becomes necessary to suggest and discuss, more or less fully, some of the influences which are in operation in modern modes of education and habits of life, and which have a special tendency to create this condition of the brain. I shall first refer to some points in connection with present methods of education as related to the young. CHAPTER V. THE INFLUENCE OF EDUCATION. The highest conception of an education would include the idea of its being symmetrical; that is, that the psychical and physical should be trained together and in harmony; that the system should be considered and educated as a whole, the brain not being stimulated in its cultivation at the expense of the body, or neglected while the latter is in process of development. If both are educated together, and with due proportion of attention to the laws of development and growth of each, then they will be in the most favorable condition to withstand the effects of the wear and tear which come in the lives of all. That the courses of education at present pursued in the larger number of our select and common schools, especially those located in cities and large towns, are of this character, will hardly be claimed by persons who study educational systems and processes from a physiological and sanitary point of view. At five or six years of age, and while for some years the system must be in the formative, growing period of its existence, the child is confined five hours a day on a hard seat or chair, in a room often illy ventilated and irregularly heated. During the larger portion of this time he or she is expected to have the mind occupied in study, or recitation, which is quite equivalent to study. In addition to this, after the child arrives at the age of ten or twelve years, tasks of such extent and difficulty are imposed, that it becomes necessary to study one or two hours during the evening. I think that most persons, with much experience in intellectual occupations, will agree with me, that six hours a day are quite enough for an adult mind to be occupied, with advantage, in study. I am confident it will be found that our most successful clergymen, lawyers, and _littérateurs_, though at times a more protracted period of mental effort may be necessary, yet, as a rule, do not spend a longer period daily in intellectual efforts.