THE CAUSATION OF DISEASE. 23 



— i.e., through the vasomotor system, trophic nerves, and so 

 forth. (2) The mind indirectly affects the individual cell-E 

 of the body through its power of regulating the external- 

 body-E. A very large number of diseases are caused by an 

 improper mental regulation of this external -body-E. (For 

 the present, however, I wish to confine myself to the internal 

 cell E ; the external bodily E will require separate considera- 

 tion.) 



Owing to the dominant influence which the nervous system 

 wields over the other tissues, it often happens that a disease 

 originates in it, although this connection entirely escapes our 

 observation. Of late years, several disorders, which the older 

 writers would never for one moment have thought of associ- 

 ating with the nervous system, have been traced primarily to 

 it, such as gout, rheumatism (?), and diabetes, not to mention 

 Charcot's disease, perforating ulcer, rheumatoid arthritis, and 

 such like disorders. 



I do not propose to exhibit, in any further detail, the in- 

 fluence of the various tissues upon one another, an influence 

 which, as we have seen, is due to the power which one tissue 

 possesses of modifying the cell-E of another. My object has 

 simply been to emphasize the fact. 



Now, the various parts of the bodily machinery being thus 

 closely connected, it becomes almost impossible to get one 

 portion unhinged without throwing the entire machine out of 

 gear, and here we may fairly ask, How far is it possible to get 

 a strictly local disease ? A disease may remain strictly local. 

 This happens in many surgical disorders, such as a slight 

 wound or dislocation, or a benign tumour situated in some 

 part of the body, such as the buttock, where its influence is 

 incapable of being reflected far and wide. It is possible, too, 

 to get a small patch of atheroma which shall exert no remote 

 effects. Most local diseases of this kind are, however, capable 

 of causing more or less general trouble : an atheromatous patch 

 may develop into an aneurism, a slight scratch may lead to 

 tetanus or pyaemia, and a dislocation to much general discom- 

 fort. It is well to remember, moreover, that many disorders 

 which are apparently strictly local, are not really so ; thus 

 cataract, by damaging eyesight, may lead to considerable 



