126 MAN THE ANIMAL 



geneous or helpful than any other group in their opinions about 

 how social advantage is to be taken of easier methods of getting 

 the collective living. Generally opinion regarding the problem 

 is saturated with emotion and sentiment, and that in great part 

 accounts for its wide diversity. Propaganda is substituted for 

 rational analysis, and only tiresome confusion results. 



Certain objective realities that exist now, however, have 

 bearing on the alterations of the social pattern that may occur. 

 The first and most important of these is the high average density 

 of world population. Maximum social benefit will never accrue 

 from a condition of plenty, if population is always maintained at 

 a level where in actual ^practice it presses close upon the then 

 existing possibilities of bare subsistence. The average individual 

 enjoyment of plenty will be greater and keener if there are 

 fewer individuals to divide it among. There is at the present 

 moment an almost universal tendency to reduce the total popu- 

 lation of the world through the reduction of human fertility. 

 This tendency is being accelerated by the ever wider spread of 

 the practice of more and more effective techniques of contracep- 

 tion. There is good reason to suppose that within a century or 

 less knowledge of such techniques will be nearly or quite uni- 

 versally disseminated. Probably within that time such techniques 

 will be taught universally in the schools in all civilized countries, 

 as they now are or very shortly will be in Sweden. The prev- 

 alent idea that this will result in extinction by depopulation 

 does not seem likely to the student of mammalian biology. What 

 appears infinitely more probable is that mankind will use 

 contraception as one agent of self-regulation of the total popu- 

 lation to a level where the maximum of social benefits accruing 

 from a condition of plenty may be enjoyed. 



Secondly, there is a definitely increasing aggregate conscious- 

 ness that the social burden of the biologically unfit, degenerate 

 and worthless portions of humanity is becoming intolerable, 

 and that their further breeding will have to be stopped. Sensi- 

 ble men are not likely indefinitely to permit a great part of the 

 plenty that might be enjoyed by the fit wasted on a growing 



