The human body is incomparably more complex and delicate than any machine, yet it is a widespread superstition that one skilled in the art of locating disorders (diagnosis) can, almost invariably, correct them by the magical effect of drug applications. This is a superstition with no more foundation in fact than the parallel one that a man of vicious character can be made virtuous by a magical process. He may turn from vice to virtue in a moment, but he can become spiritually strong and wholesome only by growth, and by conformity to the moral law. In like manner bodily health comes not by magic, but by right living, by conformity to the laws of health. [Sidenote: Involuntary functions are perfectly performed] It is literally true that "the only perfectly performed functions of the body are the involuntary or the automatic functions." Those that are even partly under the control of the will, such as breathing, are almost invariably ill done. The infinite wisdom is strikingly exemplified in the fact that the vital functions are quite independent of our volition except for "hindrances or ruinous urgence." We may, and we do hinder them constantly, and we subject them to "ruinous urgence" almost continuously. These two facts are responsible for nearly all the bodily ills from which we suffer. [Sidenote: Nature's marvelous methods beyond our comprehension] The marvelous metabolism by which energy is translated into life, by Nature's processes, is not only beyond our control, but beyond our comprehension. We should make it an invariable rule, therefore, never to interfere in any way, but to confine our efforts to the task of supplying Nature with material with which to do her wonderful work, and to an observance of the common laws of health and life. [Sidenote: The blood-corpuscles like little workmen] The blood-corpuscles are like millions or tens of millions of little workmen in the body, each with a particular work to do; each on duty and quickly responsive to call every moment. When we recognize the fact that the body is constantly being broken down and rebuilt; that every atom of broken-down material must be floated away in the blood, and new atoms built in to keep the structure from deterioration; that all the broken-down material is poisonous, and must be eliminated from the body without delay, we realize that the internal activities are almost bewildering. When we consider that all the blood in the body passes through the heart every two or three minutes, carrying food to every cell, and at the same time carrying away the poisonous products of physical and mental activities, disposing of them by various processes; when we remember that the supply to every cell is delicately adjusted to constantly varying requirements; that all this goes on so quietly and so smoothly that we are unconscious of it--when we remember all this, we begin to have some appreciation of the Psalmist's exclamation, "I am fearfully and wonderfully made."