106 PSYCnOLOGT. 



your back teeth and bite hard : you think you feel the Ja"W 

 move and the front teeth approach each other, though in 

 the nature of things no movement can occur.* — The visu- 

 al suggestion of the path traversed by the finger-tip as the 

 locus of the movement-feeling in the joint, which we dis- 

 cussed on page 41, is another example of this semi-hallu- 

 cinatory power of the suggested thing. Amputated people, 

 as we have learned, still feel their lost feet, etc. This is a 

 necessary consequence of the law of specific energies, for if 

 the central region correlated with the foot give rise to any 

 feeling at all it must give rise to the feeling of a foot, f But 

 the curious thing is that many of these patients can will the 

 foot to move, and when they have done so, distinctly /ee? the 

 movement to occur. They can, to use their own language, 

 * work ' or ' wiggle ' their lost toes. X 



Now in all these various cases we are dealing with data 

 which in normal life are inseparably joined. Of all possi- 

 ble experiences, it is hard to imagine any pair more uni- 

 formly and incessantly coupled than the volition to move, 

 on the one hand, and the feeling of the changed position of 

 the parts, on the other. From the earliest ancestors of ours 

 which had feet, down to the present day, the movement of 

 the feet must always have accompanied the' will to move 

 them ; and here, if anywhere, habit's consequences ought 

 to be found.! The process of the willing ought, then, to pour 

 into the process of feeling the command effected, and ought 

 to awaken that feeling in a maximal degree provided no 

 other positively contradictory sensation come in at the same 

 time. In most of us, when the will fails of its effect there 

 is a contradictory sensation. We discern a resistance or 

 the unchanged position of the limb. But neither in anaes- 

 thesia nor in amputation can there be any contradictory 

 sensation in the foot to correct us ; so imagination has all 

 the force of fact. 



* Pfliiger's Arcbiv, xxxvii. 1. 

 f Not all patients have this additioDal illusion. 



X I ought to say that in almost all cases the volition is followed by 

 actual contractioD of muscles in the siumj). 



