584 PSYCHOLOGY. 



spiritual quality of tliem seems a codeterminant of tlieir 

 mechanical effectiveness. If the mechanical activities in a 

 cell, as they increase, give pleasure, they seem to increase 

 all the more rapidly for that fact ; if they give displeasure, 

 the displeasure seems to damp the activities. The psychic 

 side of the phenomenon thus seems, somewhat like the ap- 

 plause or hissing at a spectacle, to be an encouraging or ad- 

 verse comment on what the machinery brings forth. The soul 

 presents nothing herself ; creates nothing ; is at the mercy 

 of the material forces for all possibilities; but amongst 

 these possibilities she selects; and by reinforcing one and 

 checking others, she figures not as an ' epiphenomenon,' 

 but as something from which the play gets moral support. 

 I shall therefore never hesitate to invoke the efficacy of the 

 conscious comment, where no strictly mechanical reason 

 appears why a current escaping from a cell should take 

 one path rather than another.* But the existence of the 

 current, and its tendency towards either path, I feel bound 

 to account for by mechanical laws. 



Having now considered a nervous system reduced to its 

 lowest possible terms, in which all the paths are connate, 

 and the possibilities of inhibition not extrinsic, but due 

 solely to the agreeableness or disagreeableness of the feeling 

 aroused, let us turn to the conditions under which new paths 

 may be formed. Potentialities of new paths are furnished 

 by the fibres which connect the sensory cells amongst 

 themselves ; but these fibres are not originally pervious, 

 and have to be made so by a process which I proceed hy- 

 pothetically to state as follows : Each discharge from a sen- 

 sory cell in the forward direction f tends to drain the cells lying 

 behind the discharging one of ivhatever tension they may possess. 

 The drainage from the rearioard cells is ivhatfor the first time 

 makes the fibres pervious. The result is a newformed ^'path^ 

 running from the cells lohich loere ' rearivard ' to the cell ivhich 

 was 'forioard' on that occasion; ivhich path, if on future occa- 

 sions the rearward cells are independently excited, ivill tend to 

 carry off their activity in the same direction so as to excite th£ 



* Compare Vol. I. pp. 137, 142. 



f That is, the directiou towards the motor cells. 



