_The Moral Sense._—From fifteen to twenty-five years of age is the most crucial period of life in regard to the hygiene of the mind. It is during this period that the brain first exhibits some of its strongest hereditary tendencies. While such mental factors in human life as conduct and character are being consolidated, as they now are, hereditary predispositions manifest themselves, telling for good or evil, for success or failure. The acquisitions then made are critical in the extreme and often final. The real love of right, hatred of wrong, duty, conscience, religion, become solid and effective in forming character. The emotional nature instinctively shows a leaning toward the opposite sex; love between the sexes toward the close of adolescence is the most intense and most unreasoning of human passions. The sense of right, wrong, and duty become active principles, dominating the character. There are yearnings after the ideal, an intense scorn of and hatred of evil. The purposes in life are then shaped. The impressions and resolutions then formed affect the whole tenor of the woman’s life, as a rule, more than at any other time. The capacity to feel pleasure reaches its greatest intensity. The sex relations are built up on safe and natural lines, regulated by family life, social feelings, and the carrying of the thoughts and the emotions into other channels, controlled by certain instinctive natural tendencies, by morality and religion. To think and feel properly should mean to act rightly as a physiologic corollary. Music, literature, and art, imaginative works of all sorts, mix themselves up with the sex feeling, so that the two help to form the emotional nature. Far-away glimpses of poetic feeling, pleasurable altruism, citizenship, and patriotism show themselves in the earlier stages and give direction to life in the later. The whole period is one of immense importance for the health and happiness of the remainder of life, and the risks to the body and mind are then very great. A fact which is of great importance, and which is especially true of adolescence, is that it is possible by undue pressure to use up stores of energy that should have been spread out over very long periods. Through such overexertion in study or in games too heavy a drain is made on futurity, and mental disorders at this time are by no means infrequent, mental depression being generally the first to appear. This is more especially true in the descendants of neurotic families. The subjects are troubled with neuralgias, insomnias, and there is a pessimistic view taken of life.