MEASURES TO ENCOURAGE FERTILITY OF GIFTED 355 



It is practically impossible to select all gifted persons by intelligence tests. 

 We must, therefore, be satisfied with the attainable and apply the measures 

 suggested to that group of the population in which a relatively large number 

 of able people are found. As we have seen from the foregoing that in the 

 social upper classes the number of intellectual children (I.Q. above 120) al- 

 though not 100 per cent is still considerably greater than in the other classes, 

 the measures to promote the fecundity of the gifted amount in practice to 

 the encouragement of the fertility of the upper classes. 



10. Statistics show the fecundity is lowest among the higher social classes. 

 This fact has been observed everywhere. We need only recall in this 



connection the research work of Fahlbeck, Bertillon, Mombert, Brentano, 

 Wolf, Pearl, Burgdorfer and so many others. Lenz writes that formerly 

 positive social selection went together with positive biological selection. 

 Nowadays it is exactly the reverse. The intellectual classes of the popula- 

 tion marry at a more advanced age, they have a smaller number of children 

 than the less educated classes. Positive social selection goes together with 

 a negative biological selection. To lose the biological race may actually 

 mean victory in the social contest. The circumstance that family limita- 

 tion may lead to social advancement is an inducement to restrict the size of 

 the family. People are willing to lose from a biological point of view for 

 the sake of social victory; worse, the loss is a means thereto. Thus social 

 selection, under the modern way of looking at life becomes the cause of a 

 biological contraselection in grand style. In practice it amounts to this: 

 the intellectually gifted are more numerous amongst the upper classes than 

 amongst the lower classes, while it is precisely among the upper classes that 

 the lowest number of children is registered. The irrefutable result is, there- 

 fore, that if fecundity continues in the same proportion, the intellectuals 

 poor in children, will be, in a few generations, in a great minority; to all 

 intents and purposes they will have disappeared and we shall then have a 

 predominance of the less gifted with numerous children. 



11. In recent years, however, various investigations have shown that the fe- 

 cundity of the social lower classes of the population has not only substantially 

 declined but is here and there even lower than amongst the upper classes. 



I would mention in the first place the researches of Prof. Edin of Stock- 

 holm who found that, since the war, the birth rate in the labour districts was 

 lower than in the well-to-do districts. Further the reports of Grotjahn at 

 the World Population Conference held in Geneva in 1927, the publication 

 of Bierens de Haan in 1924, that of Wolf in 1928, the important results of 

 Prof. L. Hersch with regard to the birthrate in Paris in the different "arron- 

 dissements" (borough-districts) in relation to the degree of prosperity. In 



