i MENTAL EVOLUTION 13 



social forces at work in the psychology of the higher 

 animals which live, some in herds or swarms or flocks, some 

 in families of greater or less permanence. There are also 

 individual and racial differences among men which affect 

 their capacity for supporting or advancing the social tradi- 

 tion, and the question whether actual human faculty the 

 average equipment with which the individual is furnished 

 by physical heredity improves with civilisation is an 

 important question. But it is not the main question with 

 which we have to deal in tracing the growth of the social 

 mind. With no change at all in the average hereditary 

 individual capacity in a group, the very greatest changes 

 might be brought about in the course of a few generations 

 by social forces ; and the probability is that the greater 

 changes of history, including both the rise and the fall of 

 nations and of civilisations, are attributable to such social 

 causes and not to sudden variations in the average heredi-' 

 tary qualities of races. 



Be this as it may, it is to be understood from the outset 

 that the scope of our enquiry includes the social along with 

 the individual. Could it ever be fully carried out it would 

 begin with the most rudimentary germs of mental activity 

 discoverable in the lowest organisms : it would trace the 

 successive stages of mental growth in the higher orders of 

 the animal creation till it reached the beginnings of human 

 intelligence ; and thence proceeding essentially by the same 

 method, but concerning itself now for the most part with 

 social forces and social products, it would follow the 

 successive stages in the movement of human thought from 

 its first beginnings to that phase of development in which 

 we live and in which we share. The data for such an 

 enquiry are not and perhaps never will be complete. Our 

 conception of the lowest phases of mind is necessarily 

 inferential, and the path of inference here is surrounded by 

 many pitfalls. Our knowledge of the earlier societies is 

 scanty and at some important points altogether wanting. 

 But in all this we suffer no more than biology suffers from 

 the imperfection of the geological record, and though we 

 may never be able to paint an accurate picture of mental 

 evolution as a whole, there is no reason why we should not 



