190 UNIVERSAL EVOLUTION 



neural structure essential to this correspondence; but 

 has no knowledge, until experience establishes certain 

 relations of space, time, quantity, and quality, from 

 which the present sensation can summon images of 

 memory. By the fusion of the two images, a true one 

 is obtained. That is knowledge. 



These experiences are the rearrangement of the 

 molecules of certain centers of the brain which pro- 

 duces the conception. This complex movement of 

 structure constitutes the idea, and the latter passes 

 away, when the pattern of moving molecules is trans- 

 formed to other patterns. The recurrence of the same 

 idea is the reformation of the same pattern on the tissue 

 of the brain. 



Of course, the process of the evolution of intellect, 

 or abstract generalization in man, is extremely complex 

 and involved. This comes only with years of experi- 

 ence, and the formation of new and higher reflex arcs, 

 in the brain. It is not the function of the brain to 

 "store up" ideas or sensations. But a stimulation, 

 often repeated, changes the more stable molecules of 

 the nerve cells, to less stable ones, and thus increases 

 the potential work, the accumulation of what we call 

 psychical processes. When this potential accumula- 

 tion is released into actual work, the product is the 

 more stable molecules, and the psychical phenomena 

 are called, e. g., memory, or imagination, etc. Thus, 

 there is always going on in the nerve structure, a 

 change of the chemical composition of molecules re- 

 sulting in either potential, or actual work. These 

 physiological functions are the psychical phenomena of 

 thought and feeling. Herbert Spencer says: "An 

 idea is the psychical side of what, on its physical side, 

 is an involved set of nervous plexuses. That which 



