408 FRAGMENTS OF SCIENCE. 



think or feel when it runs into frost-ferns upon a 

 window pane ? If not, why should the molecular 

 motion of the brain be yoked to this mysterious com- 

 panion consciousness ? We can form a coherent 

 picture of all the purely physical processes the stirring 

 of the brain, the thrilling of the nerves, the discharging 

 of the muscles, and all the subsequent motions of the 

 organism. We are here dealing with mechanical pro- 

 blems which are mentally presentable. But we can 

 form no picture of the process whereby consciousness 

 emerges, either as a necessary link, or as an accidental 

 by-product, of this series of actions. The reverse pro- 

 cess of the production of motion by consciousness is 

 equally unpresentable to the mind. We are here in 

 fact on the boundary line of the intellect, where the 

 ordinary canons of science fail to extricate us. If 

 we are true to these canons, we must deny to sub- 

 jective phenomena all influence on physical processes. 

 The mechanical philosopher, as such, will never place 

 a state of consciousness and a group of molecules 

 in the relation of mover and moved. Observation 

 proves them to interact ; but, in passing from the one 

 to the other, we meet a blank which the logic of deduc- 

 tion is unable to fill. This, the reader will remember, is 

 the conclusion at which I had arrived more than twenty 

 years ago. I lay bare unsparingly the central difficulty 

 of the materialist, and tell him that the facts of observa- 

 tion which he considers so simple are ' almost as diffi- 

 cult to be seized mentally as the idea of a soul.' I go 

 further, and say, in effect, to those who wish to retain 

 this idea, ' If you abandon the interpretations of grosser 

 minds, who image the soul as a Psyche which could 

 be thrown out of the window an entity which is 

 usually occupied, we know not how, among the molecules 

 of the brain, but which on due occasion, such as the 



