pain is not the cause of action, is I 

 think evident. Nervous motions, in- 

 duced by the will, cause our mus- 

 cles to act, but such motions oc- 

 casion no sensation in the obedient 

 muscles. When, therefore, we employ the 

 terms in common use of a stimulus being 

 applied, and an action or disease excited, 

 \ve should remember that neither the in- 

 fliction of pain, nor absolute injury, is 

 essential to the production of such con- 

 sequences. 



With respect to the second proposition, 

 into which I have resolved the objections 

 that may be made to Haller's opinion 

 of irritability being independent on sen- 

 sibility, I have only to remark, that the 

 effects of pressure made on nerves, as 

 well as other observations, have induced 

 the general belief that some fluid or 

 energy pervades the nerves for the supply 

 of the body. Pressure on a nerve be- 



