THE WONDERS OF LIFE 



ference in the complicated fibrils which ejctend in the 

 cytoplasm of both organs ^ although our coarse means 

 of investigation have not yet succeeded in detecting 

 this difference. In order to distinguish properly be- 

 tween the two sets of neurona, I propose to call the 

 sensory -cells or sense-centres wsihetal cells, and the 

 thought-cells or thought-centres phronetal cells. The 

 former are, anatomically and physiologically, the intef- 

 mediaries between the external sense-organs and the 

 internal thought-organs. 



To this anatomic delimitation of the internal sense- 

 centres and thought-organs in the cortex corresponds 

 their physiological differentiation. The sensorium, or 

 sense-centre, works up the external sense-impressions 

 that are conveyed by the peripheral sense-organs and the 

 specific energy of their sensory nerves; the cestheta, or 

 the central sense-instruments that make up the sen- 

 sorium, and their organic units, the (esthetal cells, pre- 

 pare the sense-impressions for thought and judgment in 

 the proper sense. This work of " pure reason " is accom- 

 plished by the phronema of the thought-centres, the 

 phroneta (or the various thought-organs that compose 

 it) and their histological elements, the phronetal cells, 

 bringing about an association or combination of the pre- 

 pared impressions. By this important distinction we 

 avoid the error of the older sensualism (of Hume, 

 Condillac, etc.) — namely, that all knowledge depends on 

 sense-action alone. It is true that the senses are the 

 original source of all knowledge; but, in order to have 

 real knowledge and thought, the specific task of reason, 

 the impressions received from the external world by the 

 sense-organs, and their nerves and centres, must be 

 combined in the association-centres and elaborated in 

 the conscious thought-centres. Then there is the im- 

 portant, but frequently overlooked, circumstance that 

 there is in advance in the phronetal cells of the civilized 



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