In the Preface to the First Edition I ventured to suggest that some effective knowledge of the mind might be of value to a nation at war; I take this opportunity of suggesting that such knowledge might be not less useful to a tired nation seeking peace. At the same time it should perhaps be added that this book is concerned wholly with the examination of principles, is professedly speculative in methods and conclusions, and is quite without pretensions to advise upon the conduct of affairs. _August, 1919._ {9} CONTENTS PAGE PREFACE 5 PREFACE TO SECOND EDITION 8 HERD INSTINCT AND ITS BEARING ON THE PSYCHOLOGY OF CIVILIZED MAN INTRODUCTION 11 PSYCHOLOGICAL ASPECTS OF INSTINCT 15 BIOLOGICAL SIGNIFICANCE OF GREGARIOUSNESS 18 MENTAL CHARACTERISTICS OF THE GREGARIOUS ANIMAL 23 SOCIOLOGICAL APPLICATIONS OF THE PSYCHOLOGY OF HERD INSTINCT GREGARIOUSNESS AND THE FUTURE OF MAN 60 SPECULATIONS UPON THE HUMAN MIND IN 1915 MAN’S PLACE IN NATURE AND NATURE’S PLACE IN MAN 66 COMMENTS ON AN OBJECTIVE SYSTEM OF HUMAN PSYCHOLOGY 69 SOME PRINCIPLES OF A BIOLOGICAL PSYCHOLOGY 91 THE BIOLOGY OF GREGARIOUSNESS 101 CHARACTERS OF THE GREGARIOUS ANIMAL DISPLAYED BY MAN 112 SOME PECULIARITIES OF THE SOCIAL HABIT IN MAN 120 IMPERFECTIONS OF THE SOCIAL HABIT IN MAN 132 GREGARIOUS SPECIES AT WAR 139 ENGLAND AGAINST GERMANY—GERMANY 156 ENGLAND AGAINST GERMANY—ENGLAND 201 POSTSCRIPT OF 1919 PREJUDICE IN TIME OF WAR 214 PSYCHOLOGICAL ANTICIPATIONS 224 AFTER THE WAR 235 THE INSTABILITY OF CIVILIZATION 241 SOME CHARACTERS OF A RATIONAL STATECRAFT 251 INDEX 261 {11} INSTINCTS OF THE HERD IN PEACE AND WAR HERD INSTINCT AND ITS BEARING ON THE PSYCHOLOGY OF CIVILIZED MAN I. INTRODUCTION