And if it be true that the exercise of the social and moral faculties secures the highest degree of enjoyment, those disparities in mental powers which give exercise to the virtues of compassion, self‐denial, fortitude and benevolence in serving the weak, and the corresponding exercises of gratitude, reverence, humility and devotion in those who are thus benefited, then we can see the wisdom and benevolence of this gradation of mental capacity. Moreover, in a commonwealth perfectly organized, where the happiness of the whole becomes that of each part, whatever tends to the highest general good tends to the best interest of each individual member. This being so, the lowest and humblest in the scale of being, in his appropriate place, is happier than he could be by any other arrangement, and happier than he could be if all were equally endowed. This subject is very important, because some theologians present these disparities of mental organization as indications of the depravity consequent on Adam’s sin. CHAPTER XVII. NATURE OF MIND.—HABIT. This chapter is introduced because some theologians claim that the depravity of man consists either in _a habit_ or in something _like_ a habit. Habit is a facility in performing physical or mental operations, gained by the repetition of such acts. As examples of this in _physical_ operations may be mentioned the power of walking, which is acquired only by a multitude of experiments; the power of speech, secured by a slow process of repeated acts of imitation; and the power of writing, gained in the same way. Success in every pursuit of life is attained by oft‐repeated attempts, which finally induce a habit. As examples of the formation of _intellectual_ habits, may be mentioned the facility gained in acquiring knowledge by means of repeated efforts, and the accuracy and speed with which the process of reasoning is performed after long practice in this art. As examples of _moral_ habits may be mentioned those which are formed by the oft‐repeated exercise of self‐government, justice, veracity, obedience, and industry. The will, as has been shown, gains a facility in controlling specific volitions and in yielding obedience to the laws of right action by constant use, as really as do all the other mental powers. The happiness of man, in the present state of existence, depends not so much upon the circumstances in which he is placed, or the capacities with which he is endowed, as upon the _formation of his habits_. A man might have the organ of sight, and be surrounded with all the beauties of nature, and yet, if he did not form the habit of judging of the form, distance and size of bodies, most of the pleasure and use from this sense would be wanting. The world and all its beauties would be a mere confused mass of colors. If the habits of walking and of speech were not acquired, these faculties and the circumstances for employing them would not furnish the enjoyment they were designed to secure.