Such, if I mistake not, is the result of the simple and merely common-sense examination of the general opinion of mankind. If we investigate history, properly so called, if we inquire into the nature of the great crises of civilisation, of those facts which, by universal confession, have given it a great impulse, we shall invariably recognise one or other of the two elements I have just described. They are always crises of individual or social development, or facts which have wrought a change in the internal man, in his creeds or habits, or in his external condition, or his position in relation to his fellow mortals. For example, Christianity, not merely at its first introduction, but during the first ages of its existence, in no degree addressed itself to the social state; it proclaimed aloud that it did not interfere with it; it ordered the slave to obey his master; it attacked none of the great evils and iniquities of the society of that period. Who, however, will deny that Christianity, from the first, was a great crisis in civilisation? Why? Because it changed the internal man, the prevailing principles and sentiments, because it regenerated the moral and intellectual man. We have witnessed a crisis of another nature, one which was addressed, not to the internal man, but to his external condition, which has changed and regenerated society. That, likewise, was assuredly one of the decisive crises of civilisation. Run through the whole of history, you will everywhere find the same result: you will not discover any important fact aiding in the development of civilisation, which has not exercised one or other of the two sorts of influence which I have mentioned. {32} Such is, I conceive, the natural and popular meaning of the term; and we have the fact, I will not say defined, but described and exemplified almost completely, or at least in its general features. We understand the two elements of civilisation. Now, we ask ourselves, Whether one of these two things suffices to constitute it--whether, if the development of the social state, or that of the individual man, be presented in disjunction, there would be civilisation? Would the human race recognise it as such? or is there between the two facts so intimate and necessary a relation, that if they are not simultaneously produced, they are notwithstanding inseparable, and the one draws on the other sooner or later? It appears to me we may approach this question on three sides. We may examine the real nature of the two elements of civilisation, and inquire whether by that alone they are closely united, and mutually necessary or not? We may institute a historical search to ascertain if they have, in reality, been made manifest separately, or if they have always produced each other. We may finally consult the general opinion of mankind, common sense. I will first address myself to the general opinion.