thought--Modern belief in the power of crowds--It transforms the
traditional policy of the European states--How the rise of the
popular classes comes about, and the manner in which they
exercise their power--The necessary consequences of the power of
the crowd--Crowds unable to play a part other than
destructive--The dissolution of worn-out civilisations is the
work of the crowd--General ignorance of the psychology of crowds--
Importance 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.
The first is the destruction of those religious, political, and