1 68 Life and Matter [chap. ix. 



far as energy is concerned it is the same 

 whether we sign Andrew Carnegie or 

 Alexander Coppersmith, yet the one effort 

 may land us in twelve months' imprisonment 

 or may build a library, according to circum- 

 stances, while the other achieves no result 

 at all. John Stuart Mill used to say that 

 our sole power over Nature was to move 

 things ; but strictly speaking we cannot do 

 even that : we can only arrange that things 

 shall move each other, and can determine 

 by suitably preconceived plans the kind and 

 direction of the motion that shall ensue at a 

 given time and place. Provided always that 

 we include in this category of " things " our 

 undoubtedly material bodies, muscles and 

 nerves. 



But here is just the puzzle : at what 

 point does will or determination enter into 

 the scheme ? Contemplate a brain cell, 

 whence originates a certain nerve-process 

 whereby energy is liberated with some 

 resultant effect ; what pulled the detent in 

 that cell which started the impulse ? No 



