5i8 SOCIAL ASPECTS OF BIOLOGICAL RESULTS 



recent years to define the way in which generation is linked 

 to generation. The fundamental fact of the continuity of the 

 germinal material from generation to generation — the fact which 

 is in biology like the first law of motion in physics — secures that 

 persistence and continuity of organic kinship on which the 

 possibility of a society depends. The peculiar way in which 

 the germ-plasm accumulates within itself what we must regard 

 as multiple sets of hereditary contributions, and becomes like a 

 mosaic, or like capital growing at compound interest, is a funda- 

 mental fact for sociologist as well as for biologist. It is the 

 organic condition of the social instinct. 



The great generalisation known as Galton's Law of Ancestral 

 Inheritance, according to which inheritances are on an average 

 made up of a half from the two parents, a quarter from the 

 four grandparents, an eighth from the great-grandparents, and 

 so on, may require some adjustment as regards the precise 

 fractions, and in relation to cases of inter-crossing, but the 

 general fact seems to have been well established, and it is eloquent. 

 Taking it along with Professor Karl Pearson's evidence that the 

 inheritance of psychical characters can be formulated like that 

 of physical characters, we are in a better position to understand 

 what is called ' social solidarity " and " social inertia." We 

 are able to realise more vividly how the past has a living hand 

 on and in the present, even to feel, perhaps, that there is a danger 

 of fallacy in insisting too much on either past or future when we 

 have to deal with the continuous stream of life. Mr. Galton's 

 generalisation makes reversions, survivals, recapitulations, and 

 the like more intelligible. 



Very suggestive also is Mr. Galton's elucidation of Filial 

 Regression— that there is a continual and necessary tendency 

 to approximate to the mean of any stock. In proportion as 

 two parents are divergent from the mean of their stock, will be 

 the succession-tax levied upon their offspring, which wiU tend 

 to approximate, up or down, towards the general level. This 



