THE SPINAL CORD AND CEREBELLUM 127 



There are two elements in volition — a sensory or 

 intellectual element, and an increase of impulse ; but 

 the term ' will ' is employed in a vague manner to 

 cover or express both elements. We should have 

 a very much clearer conception of things as they are 

 if we were to keep the two elements separate. We 

 call the action of the ' increase of impulse ' cells 

 ' will ' when they act in conjunction with the sensory 

 and intellectual cells of the cerebral cortex, but there 

 is no reason whatever to suppose that they do not 

 play a part — an essential and necessary part — in in- 

 voluntary action also. How, then, are we to designate 

 the ' increase of impulse ' cells under these circum- 

 stances, if our only term for them is ' will ' cells ? 



Doubtless it is true that we have a still further The 

 conception of voluntary action — a conception, be it desire. 

 said, which corresponds to certain physiological con- 

 ditions, but not to any specific class of nerve-cells. 

 When we have a desire or longing, however ardent 

 it may be, the only cells to the action of which we 

 can attribute it are, in the first place, the sensory 

 cells of the cerebral cortex, representing the idea and 

 the emotions connected with it other than will, 

 assuming that the cerebral cortex is the seat of the 

 emotions ; and, in the second place, the ' increase 

 of impulse ' cells, already mentioned, together with 

 the sensory and vaso-motor cells immediately depend- 

 ing on them. These ' increase of impulse ' cells are 

 not, however, to be found in the cerebral cortex, 

 where, beyond the cells already mentioned — that is 



