1046 ON CUTANEOUS AND [BOOK in. 



to the structures themselves but to neighbouring parts and 

 especially to the skin ; the intense pain, for instance, of " renal 

 colic," caused by the impact of a calculus in the ureter is referred 

 by us not to the ureter itself but to adjoining parts, to the cor- 

 responding somatic segment; and so in other instances. We 

 can also recognize certain characters in different pains, beyond 

 that of the mere degree of intensity ; we speak of pains as being 

 burning, aching, gnawing, cutting, throbbing and the like. But 

 in all cases the pain remains a mere sensation ; when it comes, 

 all we can say is that we feel in a particular region of the body 

 a pain of a certain intensity and having a certain character. We 

 infer that something is wrong, but the pain in no way tells us 

 what the wrong is ; we may call the pain a burning one because 

 it is more or less like the pain which we feel when the skin is 

 burnt ; but in the vast majority of cases heat has nothing what- 

 ever to do with pains of a burning character ; and so with other 

 kinds of pain, the character of the pain does not in itself tell us 

 anything about its cause. 



Are we then to regard pain as a sensation of a kind by itself, 

 the very threshold of which, the very least amount of which that 

 can in any way affect our consciousness, must be regarded as 

 already pain ? In attempting to answer this question the follow- 

 ing considerations deserve attention. 



We are in a certain obscure way aware of what we may call 

 the general condition of our body. To put an extreme case, if 

 the whole of our abdominal viscera were removed we should be 

 aware of the loss. We should be aware of this through more 

 ways than one. The tactile sensations from the abdominal skin 

 would be in such a case different from the normal, and moreover 

 the muscular sense of the abdominal walls and of all the muscles 

 whose actions bear on the abdomen, would make us aware of the 

 void. But beyond all these indirect ways, it is probable that 

 we should in a more or less obscure manner be directly conscious 

 of the loss. It is probable that sensory impulses, not of the 

 character of pain, are continually, or from time to time, passing 

 upwards from the abdominal viscera to the central nervous sys- 

 tem. These do not affect our consciousness in such a distinct 

 manner as to enable us to examine them psychologically in the 

 same way that we are able to examine special sensations such as 

 those of sight, or even sensations of pain ; they are even less 

 well defined than those of the muscular sense ; nevertheless they 

 do enter, though obscurely, into our consciousness, so that we 

 become aware of any great change in them, and they have 

 been spoken of under the title of "common" or "general sensi- 

 bility." In discussing the manner in which the manifold coor- 

 dinate movements of the body were carried out we saw reasons 

 for thinking that the central processes of the nervous sys- 

 tem were largely determined by varied afferent impulses which 



