THE EVOLUTION OF MAN 



of motion in physics and chemistry. In the chain 

 of cause and effect, feeling is only followed by 

 feeling and motion by motion. The place of a 

 link in one series is never taken by a member of 

 the other series. The attempt to substantiate 

 this statement in detail would lead too far away 

 from our subject. Suffice it to indicate that the 

 distinction between feeling and motion must be a 

 fundamental demand of every refined and work- 

 able theory of understanding. And an ignoring 

 of this demand would carry us into a fatal laby- 

 rinth of ideas. It may seem at the first glance 

 that this statement kills the idea of "spontaneous 

 generation" with one blow. But this is by no 

 means the case. 



It hits merely the crude conception of it. In 

 order to give it a more refined and impregnable 

 form, it is necessary to extend somewhat our 

 definition of the "inorganic," that is to say, of 

 nature below the first living cell. We may then 

 maintain our hypothesis that the first cell, the first 

 genuine living being, arose on this earth through 

 natural development, when the surface of the 

 globe had cooled to a certain temperature, and it 

 originated out of the so-called inorganic sub- 

 stances of the earth which had long been pres- 

 ent. We have only to add that these substances 



144 



