THE STATUS OF MAN. 259 



crossing, whereas it is wholly immaterial what the nature of 

 these causes happens to be. Geographical isolation keeps a 

 group of organisms separate from other species, but geograph- 

 ical isolation is not a factor we are concerned with in the in- 

 stance of our two dogs. In this case the breeders of the dogs, 

 who control the choice of mates, sufficiently influence the pro- 

 portion of inter-specific matings to intra-specific ones. This is a 

 case where it is not only the constitution of the group, but 

 clearly also the situation which makes it a species. It is not the 

 nature of the different t actors which reduce variability or 

 which produce it, with which we are concerned, but wholly the 

 proportion between these two groups of factors. 



In certain species the factors which produce a preponderant 

 number of intra-specific matings as compared to crosses, are to 

 a great extent social factors. 



This is notably true for human group, human species, but 

 we saw it is equally true for some domestic animal species. 



A clear understanding of the status of mankind would ob- 

 viously be of great importance for a dispassionate discussion of 

 questions of a political nature. There exists a regrettable lack 

 of cooperation between Political philosophy and Genetics. 

 Genetics, as far at it has interested itself in man, as Eugenics, 

 has consistently concerned itself with the inheritance of details 

 of qualities of individuals, with the inheritance of epilepsy, of 

 supernumerary fingers, and has hardly ever discussed the 

 influences which cause the grouping of individuals. It has 

 looked upon such causes as upon things which do not affect the 

 evolution of man, and has left a study of them to political 

 science. Political philosophy, on the other hand, has been too 

 prone to overlook the possibility, that within a nation there 

 could be discoverable genetic differentiation not only, genetic 

 differences between individuals, but differences between group 

 of individuals. 



And just as the foundations of Eugenics are failing, where 

 they should include a study of the causes, environmental and 

 other, which underly grouping of individuals, social science 



