DH. IV.] MATTER AND SPIRIT. 437 



will assert, tliat, under terrestrial conditions, we have any 

 experience of psychical manifestation apart from physical 

 structure. When, therefore, some speculative physiologist 

 singles out one of the most important chemical ingredients 

 of brain-substance, and tells us that there is no thinkinfj 

 done without that chemical ingredient, we have no good 

 ground either for rejoicing over increased wisdom, or for 

 alarm at possible conclusions. The conclusions to be drawn, 

 whatever they may be, remain just the same as before. 

 Vision is essentially a psychical process ; yet no one pretends 

 that vision can be accomplished without an eye. If I were 

 to proclaim on the house-tops, " No vision without retinal 

 rods," would not the common-sense of mankind either rebuke 

 my audacity in pretending that I had got possession of a 

 new and wonderful truth, or derisively inquire my reasons 

 for making so much outcry over such a manifest platitude? 



The case remains entirely unaltered when we come to such 

 a minute comparison of psychical manifestation and brain- 

 action as was indicated in our chapter on the Evolution of 

 Mind. "Whatever theory be held with regard to a future 

 life, he who admits that during the present life mental 

 action in the gross is correlated with brain-action in the 

 gross, can in no wise complaiu of an attempt to trace out 

 the detailed correlations between mental action in the little 

 and brain-action in the little. If the brain is the organ of 

 Mind, and if the daily manifestations of Mind, in all their 

 complexity, are conditioned by the possession of such a 

 complex organ, then the simple ultimate elements of which 

 the complex mental manifestations are made up, must be 

 severally conditioned by the simple ultimate elements, struc- 

 tural and functional, which make up the complex organ and 

 its molecular activities. In proceeding to trace out these 

 simple ultimate correlations, we are merely analyzing two 

 complicated groups of phenomena into their elements, in 

 order that we may arrive at a better practical understanding 



