women as lower animals belonging to all the members of the tribe, and those who have made them the object of a chivalrous cult; between those who expose their malformed children to perish, and those who lodge their idiots and incurables in magnificent hospitals—we trace out the close bonds which connect, through the ages, the most different thoughts, institutions, and creeds. We realize that present civilizations have been derived from past civilizations, and contain in the germ all the civilizations to come. The evolution of thoughts, religions, industries, and art—in short, of all the elements that enter into the constitution of a civilization—is as regular and inevitable as that of the different forms of an animal series.
The factors that determine the birth and development of the constituent elements of a civilization are as numerous as those which control the development of a living being. The study of them has as yet hardly begun; but the influence of some of them can be brought into evidence. One of the most important among these factors is race—that is, the aggregation of the physical, moral, and mental traits that characterize a people.
When human races appear in history they have generally already acquired marked characteristics, which afterward undergo only very slow transformations. The oldest Egyptian bas reliefs, on which are depicted the various types of the peoples with whom the Pharaohs had to do, are proof that our present grand characterizations of races could have been applied even then, in the dawn of history.
The various human races had formed themselves during the hundreds of thousands of years that preceded historical times. They were so formed, no doubt, like all the animal species, by means of slow changes produced by variability of the environment, limited by selection and enforced by heredity. The first step toward understanding the history of a people and the origin of their institutions, moral ideas, and creeds, is to study their mental constitution. It is vain to ask from anatomical characteristics, as has been done for a long time, for the means of differentiating races. Psychology alone permits a precise definition of racial distinctions. It shows us that peoples of similar mental constitution will have similar fates when placed in like circumstances, however they may differ in external aspect. In this way we have been able to make a rational comparison between the modern English and the ancient Romans. There exists, in fact, an evident mental relationship between these two peoples; the same indomitable energy of character, the same respect for their institutions, the same capacity for conquering people and for holding colonies. But, regarding the external type, there is a complete want of resemblance between the two peoples.