356 FRAGMENTS OF SCIENCE. 



It is no explanation to say that the objective and 

 subjective effects are two sides of one and the same 

 phenomenon. Why should the phenomenon have two 

 sides ? This is the very core of the difficulty. There 

 are plenty of molecular motions which do not exhibit 

 this two-sidedness. Does water 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 companion consciousness? 

 We can form a coherent picture of the physical pro- 

 cesses the stirring of the brain, the thrilling of the 

 nerves, the discharging of the muscles, and all the sub- 

 sequent mechanical motions of the organism. But we 

 can present to our minds no picture of the process 

 whereby consciousness emerges, either as a necessary 

 link or as an accidental by-product of this series of 

 actions. Yet it certainly does emerge the prick of a 

 pin suffices to prove that molecular motion can produce 

 consciousness. The reverse process of the production of 

 motion by consciousness is equally unpresentable to the 

 mind. We are here, in fact, upon the boundary line of 

 the intellect, where the ordinary canons of science fail 

 to extricate us from our difficulties. If we are true to 

 these canons, we must deny to subjective phenomena all 

 influence on physical processes. Observation proves 

 that they interact, but in passing from one to the 

 other, we meet a blank which mechanical deduction is 

 unable to fill. Frankly stated, we have here to deal 

 with facts almost as difficult to seize mentally as the 

 idea of a soul. And if you are content to make your 

 * soul ' a poetic rendering of a phenomenon which re- 

 fuses the yoke of ordinary physical laws, I, for one, 

 would not object to this exercise of ideality. Amid 

 all our speculative uncertainty, however, there is one 

 practical point as clear as the day ; namely, that the 



