It is also plain, say the critics of our civilization, that society to-day cannot be regenerated by barbarians. To-day the whole world is practically one great civilization, with a scattering of degraded and dying little tribes here and there. Modern civilization seems to have foreseen the danger of being overrun some day as the ancient civilizations were, and to have forestalled the danger by the inventions of gunpowder and rum, syphilis and tuberculosis. Are these critics right? I believe that they are, as far as they go; I believe that to-day our civilization is rapidly degenerating; but also I believe that it contains within itself two forces of regeneration which were lacking in old societies, and which are destined ultimately to prevail in our own. The first of these forces is democracy, and the second is science. To whatever department of human activity one turns at the present day, he finds men engaged in combating the age-long evils of human life with the new weapon of exact knowledge; and their discoveries no longer remain the secrets of a few—by the agencies of the public school and the press they are spreading throughout the whole world. Thus, a new science of economics having been worked out, and the causes of poverty and exploitation set forth, we see a world-wide and universal movement for the abolition of these evils. And hand in hand with this goes a movement of moral regeneration, manifesting itself in a thousand different forms, but all having for their aim the teaching of self-mastery—the replacing of the old natural process of the elimination of the unfit by a conscious effort on the part of each individual to eliminate his own unfitness. We see this movement in literature and art; we see it in the new religions which are springing up—in Christian Science, and the so-called “New Thought” movements; we see it in the great health movement which is the theme of this book, and which claims for its leaders some of the finest spirits of our times. In the state of nature man had to hunt his own food, so he was hungry when he sat down to eat. But having conquered nature, and accumulated goods, he is able to think of enjoyments, and invents cooks and the art of cookery—which is simply the tickling of his palate with all kinds of stomach-destroying concoctions. And now the time has come when he wishes to escape from the miseries thus brought upon him; and, as before, the weapon is that of exact science. He must ascertain what food elements his body needs, and in what form he may best take them; and in accordance with this new knowledge he must shape his habits of life. In the same way he has to examine and correct his habits of sleeping and dressing and bathing and exercising, in accordance with the real necessities of his body.