The Survival of the Fittest 



most favorable to progress are those which offer 

 the greatest number and variety of stimuli which 

 will continually call into action all the powers 

 of the individual. A life of ease means lack of 

 stimuli, and hence the full development of but 

 few powers. Powder and efficiency come only 

 through vigorous exercise, and strength through 

 struggle. The obstacles may be so great that it 

 is almost or quite impossible to overcome them. 

 But development can come only through the con- 

 tinual testing and training of the growing power 

 and through compelling it to accomplish to-day 

 what was impossible a year ago. The spur of 

 necessity is the beneficent as well as the essential 

 element in the education of races and individ- 

 uals, of animals and men.^ 



But why did not some ancient cat develop 

 muscle, tooth, and claw as long as these were 

 highly profitable, and then proceed to put its 

 energy into the development of a thinking brain? 

 No cat ever did this, otherwise you and I would 

 probably have not been here. Nature seems to 

 say to every group of animals: " Try whatever 



1 See Orr, H. B., "A Theory of Development and Hered- 

 ity," p. 248. Wallace, A. R., "Darwinism," close of book. 



109 



