26 BIOLOGICAL ASPECTS OF HUMAN PROBLEMS 



century have made it possible to understand phe- 

 nomena of life to which the eighteenth century fur- 

 nished no clews. Immanuel Kant was utterly 

 hostile to the mechanistic conception. In an oft- 

 quoted passage he says : "It is quite certain that we 

 cannot become adequately acquainted with organ- 

 ized creatures and their hidden potentialities by 

 means of the merely mechanical principles of nature, 

 much less can we explain them ; and this is so certain 

 that we may boldly assert that it is absurd for man 

 even to make such an attempt or to hope that a 

 Newton may one day arise who will make the pro- 

 duction of a blade of grass comprehensible to us 

 according to natural laws that have not been ordered 

 by design. Such an insight we must absolutely 

 deny to men." But Kant elsewhere admits that 

 comparative anatomy gives us a ray of hope that 

 something may be accomplished by the aid of the 

 " principle of the mechanism of nature." Would 

 not Kant have consistently widened his expression 

 of hope had he been in possession of the facts of 

 biology that are known to us to-day? 



We have, indeed, not yet reached the time when 

 reason compels us to embrace the hypothesis of a 

 vital force. So long as the biological sciences ad- 

 vance, new territories are certain to be reclaimed 

 from the gossamer kingdom of vitalism. If it ever 

 happens that science ceases to make new discoveries 

 in biology and the human mind ceases to grow in 

 capacity, the time will have come to turn seriously 



