WILL. 58^ 



■when the sound of B enters the ear, discharges into the 

 motor cell for pronouncing C, by a repetition of the same 

 mechanism as before ; and so on ad libitum. Figure 90 

 represents the entire set of jjrocesses involved. 



The only thing that one does not immediately see is the 

 reason why * under the existing conditions ' the path from 

 S" to S'' should be the stronger drainage-channel for S"'s 

 excitement. If the cells and fibres in the figure constituted 

 the entire brain we might suppose either a mechanical or a 

 psychical reason. The mechanical reason might lie in a 

 general law that cells like S^ and M^, whose excitement is in 

 a rising phase, are stronger drainers than cells like M", 

 which have just discharged ; or it might lie in the fact 

 that an irradiation of the current beyond S^ into S'' and 

 M" has already begun also ; and in a still farther law 

 that drainage tends in the direction of the widest irra- 

 diations. Either of these suppositions would be a suffi- 

 cient mechanical reason why, having once said A, we 

 should not say it again. But we must not forget that 

 the process has a psychical side, nor close our eyes to the 

 possibility that the sort of feeling aroused by incipient 

 currents may be the reason why certain of them are in- 

 stantly inhibited and others helped to flow. There is no 

 doubt that before we have uttered a single letter, the gen- 

 eral intention to recite the alphabet is already there ; nor is 

 there any doubt that to that intention corresponds a wide- 

 spread premonitory rising of tensions along the entire 

 system of cells and fibres which are later to be aroused. So 

 long as this rise of tensions /ee?s good, so long every current 

 which increases it is furthered, and every current which 

 diminishes it is checked; and this may be the chief one of 

 the 'existing conditions' which make the drainage- channel 

 from S" to S^ temporarily so strong.* 



The new paths between the sensory cells of which we 

 have studied the formation are paths of ' association,' and 

 we now see why associations run always in the forward 



* L. Lange's and Miinsterberg's experiments with 'shortened ' or ' mus- 

 cular ' reaction-time (see Vol. I. p. 432) show how potent a fact dynami- 

 cally this anticipatory preparation of a whole set of possible drainage- 

 channels is. 



