354 AN INTRODUCTION TO MODERN GENETICS 



Nature rarely takes the form of a combat between members of the 

 same species ; or at least this is only one of innumerable activities of life 

 through which natural selection acts. Moreover, it must be pointed out 

 that most wars are between national groups, and the selection which 

 takes place is a selection, not of individuals but of nations. The quaUties 

 which make a nation best fitted to survive in such a struggle have, at 

 the present day, more to do with its industrial organization and diplo- 

 matic finesse than with the biological quahty of its members. It is 

 certainly doubtful whether evolution guided by natural selection of 

 societies on such a basis leads in the direction of a social order which 

 the majority of men would consider desirable. 



The effects of war on the populations takkig part seems, a priori, 

 likely to be genetically unfavourable. It is the sane and healthy who go 

 to the front line and are killed. At least, this was the case till as recently 

 as the American Civil War,^ but the genetic effects may perhaps be 

 amehorated when the more indiscriminate modem weapons are used. 

 If war appears unlikely to produce, as an agent of natural selection, 

 results whose value is commensurate with the undoubted unpleasant- 

 ness of the process, genetics suggest no reason why it should not be 

 eliminated. There is no merit in natural selection for its own sake; it 

 had led organic evolution into paths which seem degenerate and dis- 

 tasteful to us as well as into paths we consider progressive. People who 

 wish to justify war on biological grounds must look to other fields than 

 genetics for arguments. 



7. The Control of the Genetic Composition of the Human Population 



The process of evolution has produced the most highly developed 

 object we know of — man. The power to control this process now passes, 

 thanks to genetics, into the hands of man himself. It is inevitable that 

 this power will sometime be used. The methods which must be em- 

 ployed are the province of the geneticist, and no one doubts that it is 

 to him we must turn to obtain practical advice on how certain ends are 

 to be attained. Many geneticists argue that this is the limit of their 

 special responsibilities; in the framing of an evolutionary poHcy, they 

 urge, their opinion should have no more weight than that of any other 

 citizen. In this the geneticists are perhaps too diffident. The assess- 

 ment of evolutionary value by the mass of mankind is often influenced 

 by opinions as to the correctness of which the geneticist or social 

 scientist has scientific evidence. As an example one may cite the Ger- 

 ^ Cf. Holmes 1934, Jordan and Jordan 19 14. 



