216 COMPARATIVE PHYSIOLOGY OF THE BRAIN 



of the mechanism of the associative memory can be 

 proved. We speak of conscious volition if an idea 

 of the resulting final complex of sensations is present 

 before the movements causing it have taken place or 

 have ceased. In volition three processes occur. The 

 one is an innervation of some kind which may be 

 caused directly or indirectly by an external stimulus. 

 This process of innervation produces two kinds of 

 effects. The one effect is the activity of the associa- 

 tive memory which produces the sensations that in 

 former cases accompanied or followed the same inner- 

 vation. The second effect is a coordinated muscular 

 activity. It happens that in such cases the reaction- 

 time for the memory-effect of the innervation is 

 shorter than the time for the muscular effect. When 

 some internal process causes us to open the window, 

 the activity of the associative memory produces the 

 idea of sensations which will follow or accompany 

 the opening of the window sooner than the act of 

 opening really occurs. As we do not realise this 

 any more than we realise the inverted character of 

 the retina-image, we consider the memory-effect of the 

 innervation as the cause of the muscular effect. The 

 common cause of both effects, the innervating pro- 

 cess, escapes our immediate observation as our senses 

 do not perceive it. The will of the metaphysicians 

 is then clearly the outcome of an illusion due to the 

 necessary incompleteness of self-observation. Our 

 conception of will harmonises with Miinsterberg's 

 and James's views on this subject (6, 12). I think 



