Man in the Light of Evolution 



system comes to the throne first just because it is 

 simple, fundamental, and absolutely essential to 

 life. Muscle follows in the march, more slowly 

 at first, because more complex and difficult of 

 development, and having fewer opportunities to 

 show its usefulness and capability. Later it 

 overshadows the digestive system. Similarly 

 brain and mind were developing in the lowest 

 stages. But it was a most difficult problem to 

 form a brain. It could not show its power and 

 capacity until the muscles and all the other or- 

 gans were sufficiently mature to execute its 

 decrees. 



In tracing the mental evolution of animals we 

 enter on difficult and dangerous ground. We 

 know and understand the mental actions of ani- 

 mals only by comparing them with our own. 

 Here we may easily mistake. We must use lan- 

 guage really applicable only to the mind of man 

 and higher animals concerning beings far down 

 In the scale of life. Hence we can use the words 

 knowledge, recognition, perception, motive, and 

 choice only in an exceedingly broad or even 

 figurative sense. We use these words only be- 

 cause there are no other familiar and plain terms 

 which we can substitute for them. 



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