The Logic of Evolution 



strength and agility. Slowly, but surely, mind 

 crowded muscle off the throne of the animal 

 body. The brain reigned supreme. Quaternary 

 time is the era of mind. 



There have been three dynasties in the history 

 of evolution — first that of digestion and repro- 

 duction, then that of muscle, and finally that of 

 mind. Each lower ciynasty needed, stimulated, 

 and thus ushered in, the reign of the next higher 

 power, and then became subservient to this. 

 Every higher power begins its career as the ser- 

 vant of the lower. The reign and dominance of 

 the higher power does not destroy or hamper the 

 development of the lower function. The diges- 

 tive system attains its highest development not 

 during its period of supremacy, but in its service 

 of muscle and brain. The same is true of the 

 muscles. They are not as powerful in man as 

 in some lower animals. But they are numerous, 

 varied, complex, and capable of finer and more 

 complex movements. There is no " arrest of 

 the body." It becomes continually finer, better 

 adapted to higher uses and nobler ends discov- 

 ered by the thinking brain. 



As each higher power was needed for the 

 complete use and development of the lower, the 



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