SCIENCE AND MAN. 611 



and liberated the muscular power. Whence this impulse? 

 From the center of the nervous system. But how did 

 it originate there? This is the critical question, to 

 which some will reply that it had its origin in the human 

 soul. 



The aim and effort of science is to explain the unknown 

 in terms of the known. Explanation, therefore, is condi- 

 tioned by knowledge. You have probably heard the story 

 of the German peasant, who, in early railway days, was 

 taken to see the performance of a locomotive. He had 

 never known carriages to be moved except by animal power. 

 Every explanation outside of this conception lay beyond 

 his experience, and could not be" invoked. After long 

 reflection therefore, and ceeing no possible escape from the 

 conclusion, he exclaimed confidently to his companion, 

 " Es miissen doch Pferde darin sein" There must be 

 horses inside. Amusing as this locomotive theory may 

 seem, it illustrates a deep-lying truth. 



With reference to our present question, some may be 

 disposed to press upon me such considerations as these: 

 Your motor nerves are so many speaking-tubes, through 

 which messages are sent from the man to the world; and 

 your sensor nerves are so many conduits through which the 

 whispers of the world are sent back to the man. But you 

 have not told us where is the man. Who or what is it 

 that sends and receives those, messages through the bodily 

 organism? Do not the phenomena point to the existence 

 of a self within the self, which acts through the body as 

 through a skillfully constructed instrument? You picture 

 the muscles as hearkening to the commands sent through 

 the motor nerves, and you picture the sensor nerves as 

 the vehicles of incoming intelligence; are you not bound 

 to supplement this mechanism by the assumption of an 

 entity which uses it? In other words, are you not forced 

 by your own exposition into the hypothesis of a free human 

 soul? 



This is fair reasoning now, and at a certain stage of the 

 world's knowledge it might well have been deemed con- 

 clusive. Adequate reflection, however, shows that instead 

 of introducing light into our minds, this hypothesis con- 

 sidered scientifically increases our darkness. You do not 

 in this case explain the unknown in terms of the known, 

 which, as stated above, is the method of science, but you 



