I may mention that the book has not yet been published in French, and is presented to the public for the first time in English dress. The English lady who collaborated with Professor Richet in its production has worked with and studied under him for some years, and it was largely owing to her persuasion that he consented to express his views publicly. She desires for the present to remain anonymous. W. D. H. _October 1908._ CONTENTS PAGE PREFACE BY PROFESSOR HALLIBURTON v INTRODUCTION 1 CHAPTER I THE NECESSARY LIMITS OF VIVISECTION 7 CHAPTER II PAIN AND DEATH 18 CHAPTER III CONCERNING ANÆSTHESIA IN VIVISECTION 31 CHAPTER IV CONCERNING EXPERIMENTATION OTHER THAN VIVISECTION 40 CHAPTER V SERVICES RENDERED TO SCIENCE AND HUMANITY BY EXPERIMENTAL PHYSIOLOGY 59 CHAPTER VI MORALITY AND VIVISECTION 72 CHAPTER VII ARE LAWS REGULATING VIVISECTION NECESSARY? 91 CHAPTER VIII VIVISECTION AND THE FUTURE OF SCIENCE 97 POST SCRIPTUM 114 APPENDIX A.--DIPHTHERIA STATISTICS 121 APPENDIX B.--BIBLIOGRAPHY 124 APPENDIX C.--THE RESEARCH DEFENCE SOCIETY 130 ILLUSTRATIONS "LA MORT." By BARTHOLOMÉ, in Père Lachaise, Paris, _Frontispiece_ PASTEUR IN HIS LABORATORY, _facing page_ 44 "L'ENFANT." In Musée du Luxembourg, Paris, " 53 INTRODUCTION The object of this book is to set forth, as impartially as possible, the reasons which militate for and against vivisection. It is, however, a physiologist who is speaking, therefore no one will be surprised that he should defend a practice which is at the basis of the science he teaches. May he be permitted, at the same time, to express the high moral esteem which he feels for all those who, nobly enamoured of a very high ideal, deny to men the right of inflicting suffering, or even death, upon animals? There is not a more generous thought than this. Without doubt it is our duty to have sympathy for, and to abstain from indifference and cruelty in our dealings with all living creatures: might does not constitute right. Man is stronger than the animal; but this superiority of power, this might, does not constitute a right to act contrary to moral obligation.