EVOLUTION OF SOCIAL STRUCTURES 845 



of the interaction of antagonistic forces. They also pass from a 

 primordial stage of great simplicity into a secondary, more complex 

 stage, and these two stages are closely analogous to the protozoic 

 and metazoic stages of biology. I call them the " protosocial " and 

 "metasocial" stages, respectively. 



If we set out with the simple propagating couple, we soon have 

 the primitive family group consisting of the parents and children. 

 The children are of both sexes, and they grow to maturity, pair 

 off in one way or another, and produce families of the second order. 

 These do the same, resulting in families of the third order, and so 

 on. After a few generations the group assumes considerable size 

 and constitutes first a horde and finally a clan. The clan at length 

 becomes overgrown and splits up into several or many clans, sepa- 

 rating more or less territorially, but usually adopting the rule of 

 exogamy, and living on comparatively peaceful terms at no great 

 distance from one another. Their mode of reproduction is exactly 

 analogous to the process of reproduction by division in the Protozoa, 

 and this is what I characterize as the protosocial stage in race- 

 development. 



But the multiplication of clans through continuous reproduction 

 in a geometrical progression, coupled with the limits prescribed by 

 the food-supply, results in the wider and wider separation of the 

 clans, until at length certain clans or hordes will have become so 

 far removed from the primary centre of dispersion as to lose all 

 connection with it. At the low stage of mental development neces- 

 sary to such a race of beings scarcely as much as a tradition would 

 ultimately remain of the existence of a primordial group from which 

 all had descended. One clan would keep budding off from another, 

 and moving out farther and farther along lines of least resistance, 

 until a great area of the earth's surface would at last become thus 

 sparsely inhabited by a multitude of clans, each knowing only the 

 few that are located nearest to it. As the dispersion takes place in 

 all directions from the original centre, or as nearly so as the con- 

 figuration of the country and the nature of the food-supply will 

 permit, those migrating in opposite directions become, after a 

 sufficient lapse of time, so widely separated from one another as to 

 constitute wholly distinct peoples. They all have languages, but 

 in time the local variations that they naturally undergo render them 

 to all intents and purposes different languages, at least so much so 

 that if individuals of these long-separated groups should chance to 

 meet, they could not understand one another. It would be the 

 same with their customs, beliefs, and religion. They would have 

 become in all essential respects different races. 



We will suppose that in the end a whole continent is thus peopled 

 with these alien hordes and clans, which would now have become 



