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.

This is the work which the leaders of the new movement are engaged upon. To quote a single instance: while I was “living as I had been living” and eating the preparations of ignorant cooks in boarding-houses and restaurants, Dr. Kellogg of Battle Creek was bringing all the resources of modern chemistry and bacteriology to bear upon the problem of the nutrition of man; taking all the foods used by human beings, and analyzing them and testing them in elaborate experiments; determining the amount of their available nutriment and their actual effect upon the system in all stages of sickness and health; the various ways of preparing them and combining them, and the effect of these processes upon their palatability and ease of digestion. Every day for nine years, so Kellogg told me, he sat down to an experimental meal designed by himself and prepared by his wife; and the result is a new dietary—that in use at the Battle Creek Sanitarium—which awaits only the spread of knowledge to change the ways of eating of civilized man.

This new health knowledge has been amassed by many workers and, as in all cases of new knowledge, there is much chaff with the grain. There are faddists as well as scientists; there are traders as well as humanitarians. It seemed to us that there was urgently needed a book which should gather this new knowledge, and present it in a form in which it could be used by the average man. There have been many books written upon this; but they are either the work of propagandists with one idea—containing, as we have proved to our cost, much dangerous error; or else the work of physicians and specialists, whose vocabulary is not easily to be comprehended by the average man or woman. What we have tried to write is a book which sets forth what has been proved by investigators in many and widely-scattered fields; which is simple, so that a person of ordinary intelligence can comprehend it; which is brief, so that a busy person may quickly get the gist of it; and which is practical, giving its information from the point of view of the man who wishes to apply these new ideas to his own case.

Michael Williams was recently persuaded to give a semi-public talk on the subject before an audience of several hundred professional and business people. He was compelled to spend the rest of the evening in answering the questions of his audience; and listening to these questions, I was made to realize the tremendous interest of the public in the practical demonstration which Mr. Horace Fletcher has given of the idea of Metchnikoff, that men and women to-day grow old before they ought to do so, and that the prime of life should be from the age of fifty to eighty. A broken-down invalid at forty-five, Mr. Fletcher was at fifty-four a marvel of strength—and at fifty-eight he showed an improvement of one hundred per cent. over his tests at the age of fifty-four; thus proving that progressive recuperation in the so-called “decline of life” might be effected by followers of the new art of health.

As a result of this address, Williams was invited by the president of one of the largest industrial concerns in the country to lecture to his many thousands of employees on the new hygiene; his idea being to place at their disposal the knowledge of this new method of increasing their physical and mental efficiency.

For business men and women, indeed, for workers of all kinds, good health is capital; and the story of the new hygiene is the story of the throwing open of hitherto unsuspected reserve-stores of energy and endurance for the use of all.

In writing upon this subject, the experiences most prominent in our minds have naturally been those of ourselves, of our wives and children, and of friends who have followed in our path. As the setting forth of an actual case is always more convincing than a general statement, we have frequently referred to these experiences, and what they have taught us. We have done this frankly and simply, and we trust that the reader will not misinterpret the spirit in which we have done it. Mr. Horace Fletcher has set the noble example in this matter, and has been the means of helping tens of thousands of his fellow men and women.