Science is good and its study ennobling, but it does not suffice for man's highest aspirations, nor for the development of his moral nature. It has never explained the mystery of a single act of his will, and can never ascend into the region of the spiritual. Man may press onward and upward in its paths never so far, and there still remains the infinite beyond. His imaginations may invade the furthest circle of planetary motion, and yet we know there remain system after system of worlds, and suns shining with ineffable light, still beyond. His questions are never answered; his longings are never satisfied, and never can be until they reach The Infinite One--the object of his worship,--the Source of light and all knowledge. His questions have ever been, whence am I? and whither do I go? and it can never satisfy his aspirations, to reply that he is from the ape, and goes to the ground, and that this ends all. There still remains to him a longing for immortality; a craving for something above and beyond what he now sees and knows, and only in the hope of this something hereafter, does he have a realization of his highest possibilities. I believe that thus far in man's experience he has been the loser, not by too much religion, but rather by his unbelief and misconceptions as to its true nature and the extent of its obligations. The plan should therefore be, for a broader, higher, and more pervading religious influence, which can come only from an intelligence educated as to his relations toward and responsibility to God, and his fellow-men. As the tendency of the laws of health and religion are in the same direction, it is not easy to understand how a religious belief, or the influences which legitimately flow from it, can be otherwise than for the highest interests of society, and the mental health of its individual members. CHAPTER XV. INSUFFICIENT SLEEP. We learn the most important lessons from observing the facts and studying the operations of nature, and it is largely by such a course that we may hope to learn the true method of either understanding or practising such courses in life as will conduce to health. From the time of birth until the body finally rests in its last sleep, the human system requires periods of repose under the conditions of sleep. The child, during the first few months of its existence, passes the larger portion of the time in this state. While in it, the brain and nervous system develop more rapidly, grow in stability, and attain capacity for activity more surely than is possible in any other.