Januaet 1, 1915] 



SCIENCE 



11 



critical studies on the subject Darwin's 

 conception still remains to-day in the main 

 what it was in his own time, a theory, a 

 logical construction, based it is true on a 

 multitude of facts, yet still awaiting ade- 

 quate experimental test. Simple though 

 the principle is, its actual effect in nature 

 is determined by conditions that are too 

 intricate and operate through periods too 

 great to be duplicated in the experimental 

 laboratory. Hence it is that even after 

 more than fifty years of Darwinism the 

 time has not yet come for a true estimate of 

 Darwin's proposed solution of the gi-eat 

 problem. 



But there is still another word to be 

 said. Too often in the past the facile form- 

 ulas of natural selection have been made use 

 of to carry us lightly over the surface of 

 unsuspected depths that would richly have 

 repaid serious exploration. In a healthy 

 reaction from this purblind course we have 

 made it the mode to minimize Darwin's 

 theory; and no doubt a great service has 

 been rendered to our study of this problem 

 by the critical and sceptical spirit of mod- 

 ern experimental science. But there is a 

 homely German saying that impresses upon 

 us the need of caution as we empty out the 

 bath lest Ave pour out the child too. This 

 suggests that we should take heed how we 

 underestimate the one really simple and 

 intelligible explanation of organic adapta- 

 tions, inadequate though it now may seem, 

 that has thus far been placed in our hands. 

 And in some minds — if I include my own 

 among them let it be set down to that 

 indiscretion at which I have hinted — the 

 impression grows that our preoccupation 

 with the problem as it appears at short 

 focus may in some measure have dimmed 

 our vision of larger outlines that must be 

 viewed at longer range; that we may have 

 emphasized minor difficulties at the cost 

 of a larger truth. To such minds it will 

 seem that the principle of natural selection, 



while it may not provide a master key to all 

 the riddles of evolution, still looms up as 

 one of the great contributions of modern 

 science to our understanding of nature. 



I have taken but a passing glance at a 

 vast and many-sided subject. I have tried 

 to suggest that the tide of speculation in 

 our science has far receded; that experi- 

 mental methods have taken their rightful 

 place of importance ; that we have attained 

 to a truer perspective of past and present 

 in our study of the problems of animal life. 

 The destructive phase through which we 

 have passed has thoroughly cleared the 

 ground for the new constructive era on 

 which we now have entered. All the signs 

 of the times indicate that this era will long 

 endure. And this is of good augury for a 

 future of productive effort, guided by the 

 methods of physico-chemical science, im- 

 patient of merely a priori constructions, of 

 academic discussions, of hypotheses that 

 can not be brought to the test of experi- 

 mental verification. The work ahead will 

 make exacting technical demands upon us. 

 The pioneer days of zoology are past. The 

 naturalist of the future must be thoroughly 

 trained in the methods and results of chem- 

 istry and physics. He must prepare him- 

 self for a life of intensive research, of high 

 specialization; but in the future even more 

 than in the past he will wander in vain 

 amid the dry sands of special detail if the 

 larger problems and general aims of his 

 science be not held steadfastly in view. For 

 these are the outstanding beacon light.s of 

 progress ; and while science viewed at close 

 range seems always to grow more complex, 

 a wider vision shows that her signal dis- 

 coveries are often singularly simple. This 

 perhaps may help us to keep alive the spirit 

 of the pioneers who led the advances of a 

 simpler age; and it is full of hope for the 

 future. 



Edmund B. Wilson 



Columbia University 



