THE ERA OF CROWDS. The evolution of the present ageThe great changes in civilisation are the consequence of changes in National thoughtModern belief in the power of crowdsIt transforms the traditional policy of the European statesHow the rise of the popular classes comes about, and the manner in which they exercise their powerThe necessary consequences of the power of the crowdCrowds unable to play a part other than destructiveThe dissolution of worn-out civilisations is the work of the crowdGeneral ignorance of the psychology of crowdsImportance of the study of crowds for legislators and statesmen. The great upheavals which precede changes of civilisations such as the fall of the Roman Empire and the foundation of the Arabian Empire, seem at first sight determined more especially by political transformations, foreign invasion, or the overthrow of dynasties. But a more attentive study of these events shows that behind their apparent causes the real cause is generally seen to be a profound modification in the ideas of the peoples. The true historical upheavals are not those which astonish us by their grandeur and violence. The only important changes whence the renewal of civilisations results, affect ideas, conceptions, and beliefs. The memorable events of history are the visible effects of the invisible changes of human thought. The reason these great events are so rare is that there is nothing so stable in a race as the inherited groundwork of its thoughts. The present epoch is one of these critical moments in which the thought of mankind is undergoing a process of transformation. Two fundamental factors are at the base of this transformation