l6 THE SOCIAL LIFE OF ANIMALS 



and traditions of people. The more widespread and 

 firmly fixed these become in the minds of living men, 

 the greater is their chance of longevity. 



The most practical achievement of our extremely 

 practical period is the habit of searching for new 

 truths and for correct interpretations of those long 

 known. The unique contribution of the present era 

 is not that made by men of business and affairs, spec- 

 tacular as it may be. Rather this age is and will 

 be known as the time of the development and ap- 

 plication of scientific methods. These contributions 

 are being made by extremely impractical research 

 workers who are supported by a tiny splinter from 

 the great block of capital gains. Money spent effec- 

 tively to this end, whether in the aid of research or 

 other creative scholarship, or in teaching the results 

 gained by research, makes the most lasting and im- 

 portant of all modern investments. The most nearly 

 permanent monument any man can erect is to have 

 influenced directly or indirectly the growth of im- 

 proved ideas and traditions among the men in the 

 street, in the factory or on the farm. 



It is in this spirit that I have undertaken to inter- 

 pret one of the significant biological developments 

 of recent years. It is my hope that from the work 

 described in these pages, all social action may have a 

 somewhat broader and more intelligent foundation. 



