How to Live | Page 2

and best conclusions on individual hygiene; (2) to ascertain the exact and special needs of the individual through periodic health examinations; (3) to induce all persons who are found to be in need of medical attention to visit their physicians.
A sad commentary on the low health-ideals which now exist is that to most people the expression "to keep well" means no more than to keep out of a sick-bed. Hitherto, the subject-matter of hygiene has been considered in its relation to disease rather than to health. In this manual, on the other hand, it is treated in its relation to (1) the preservation of health; (2) the improvement in the physical condition of the individual, and (3) the increase of his vitality. In short, the objects of the manual are positive rather than negative. It aims to include every practical procedure that, according to the present state of our knowledge, an athlete needs in order to make himself superbly "fit," or that a mental worker needs in order to keep his wits sharpened to a razor-edge. For this reason some suggestions, which might otherwise be regarded as of minor importance, have been included and emphasized. While it is true that a moderate infraction of some of the minor rules of health is not inconsistent with maintaining good health in the sense of keeping out of a sick-bed, such infraction, be it ever so moderate, is utterly inconsistent with good health in the sense of attaining the highest physical and mental efficiency and power.
Future advances of knowledge will doubtless occasion additions to, or modifications of, the conclusions stated herein, and these will form the subject of subsequent publications by the Institute.
In order that the Institute may have at its disposal the latest and most authoritative results of scientific investigations, its Hygiene Reference Board was created. The present book is the first general statement of the conclusions of this Board after a year of careful consideration. These conclusions are the joint product of the members of the Board, with the active co-operation of the Director of Hygiene of the Institute. They may fairly be said to constitute the most authoritative epitome thus far available in the great, but hitherto neglected, realm of individual hygiene.
The Chairman of the Board has exercised the function of editor, and is responsible for the order and arrangement of the material.
Friends of the Institute may help its work by spreading the ideas given in the following pages and by increasing the number of its readers. Such profits as may be received by the Institute from the sale of this book will be devoted to further philanthropic effort by the Institute.
IRVING FISHER, EUGENE L. FISK.
New York, Sept., 1915.

CONTENTS
PAGE
INTRODUCTION 1
CHAPTER?I
AIR
SECTION 1. HOUSING 7 2. CLOTHING 14 3. OUTDOOR LIVING 18 4. OUTDOOR SLEEPING 20 5. DEEP BREATHING 24
CHAPTER?II
FOOD
1. QUANTITY OF FOOD 28 2. PROTEIN FOODS 35 3. HARD, BULKY, AND UNCOOKED FOODS 40 4. THOROUGH MASTICATION 44
CHAPTER?III
POISONS
1. CONSTIPATION 51 2. POSTURE 57 3. POISONS FROM WITHOUT 64 4. TEETH AND GUMS 78
CHAPTER?IV
ACTIVITY
1. WORK, PLAY, REST AND SLEEP 89 2. SERENITY AND POISE 105
CHAPTER?V
HYGIENE IN GENERAL
1. THE FIFTEEN RULES OF HYGIENE 119 2. THE UNITY OF HYGIENE 121 3. THE OBSTACLES TO HYGIENE 126 4. THE POSSIBILITIES OF HYGIENE 135 5. HYGIENE AND CIVILIZATION 143 6. THE FIELDS OF HYGIENE 157
SUPPLEMENTARY NOTES ON SPECIAL SUBJECTS
1. NOTES ON FOOD 171 2. NOTES ON OVERWEIGHT AND UNDERWEIGHT 212 3. NOTES ON POSTURE 221 4. NOTES ON ALCOHOL 227 5. NOTES ON TOBACCO 250 6. AVOIDING COLDS 272 7. SIGNS OF INCREASE OF THE DEGENERATIVE DISEASES 281 8. COMPARISON OF DEGENERATIVE TENDENCIES AMONG NATIONS 286 9. EUGENICS 293
INDEX 325

HYGIENE REFERENCE BOARD
OF THE LIFE EXTENSION INSTITUTE, Inc.
IRVING FISHER, Chairman
Professor of Political Economy Yale University
#Statistics#
WILLIAM J. HARRIS, Federal Trade Commission, United States Government.
CRESSY L. WILBUR, M.D., Director, Division of Vital Statistics, Dept. of Health, State of New York.
WALTER F. WILLCOX, Professor of Economics and Statistics, Cornell University.
#Public Health Administration#
HERMANN M. BIGGS, M.D., Commissioner of Health, State of New York.
RUPERT BLUE, M.D., Surgeon General, U.?S. Public Health Service.
H.?M. BRACKEN, M.D., Secretary Board of Health, State of Minnesota.
J.?B. GREGG CUSTIS, President Board of Medical Supervisors, District of Columbia.
SAMUEL G. DIXON, M.D., Commissioner of Health, State of Pennsylvania.
OSCAR DOWLING, M.D., President Board of Health, State of Louisiana.
JOHN S. FULTON, M.D., Secretary Dept. of Health, State of Maryland.
S.?S. GOLDWATER, M.D., Supt., Mt. Sinai Hospital, New York.
WILLIAM C. GORGAS, Major General U.?S. Army.
CALVIN W. HENDRICK, Chief Engineer, Sewerage Commission of Baltimore.
J.?N. HURTY, M.D., Secretary Board of Health, State of Indiana.
W.?S. RANKIN, M.D., Secretary and Treasurer, Board of Health, State of North Carolina.
THEO. B. SACHS, M.D., President The Chicago Tuberculosis Institute.
JOSEPH W. SCHERESCHEWSKY, M.D., U.?S. Public Health Service.
GUILFORD H. SUMNER, M.D., Secretary--Executive Officer, Dept. of Health and Medical Examiners, State of Iowa.
GEORGE C. WHIPPLE, Professor Sanitary Engineering, Harvard University.
C.?E.?A. WINSLOW, Professor of