COSMIC PHILOSOPHY 



recompounding of impressions. If we may for 

 a moment unduly simplify the matter, it may 

 be said that for every renewed grouping of im- 

 pressions, for every revived association of ideas, 

 there is a nervous discharge between two or 

 more cells, along formerly used sets of transit 

 fibres ; and for every fresh grouping of impres- 

 sions, for every new connection of ideas, there 

 is a discharge along new transit lines. In reality 

 the matter cannot be so simple as this, since, 

 as we shall presently see, the maintenance of 

 consciousness implies a state of tension between 

 many simultaneous discharges. But however 

 great the complexity, the principle remains the 

 same. 



If it be objected to this view that it obliges 

 us to assume a vast amount of differentiation 

 and integration in the brain, during the lifetime 

 of single individuals, it may be replied that the 

 assumption is fully sustained, both by sound 

 deduction and observation. Not only does the 

 brain increase in size and heterogeneity during 

 the first twenty-five years of life, but ordinarily 

 it increases in heterogeneity, and often in size, 

 for many years later ; and in some cases it in- 

 creases in heterogeneity until the end of life. 

 The brain of a young child is in homogeneity 

 like the brain of an ape ; the furrows are shal- 

 low, symmetrical, and few in number. With 

 advancing years they increase in number, depth, 

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