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degree of susceptibility may be manifested, that the virus; 

 may run riot in his system, producing symptoms of the 

 utmost violence and intensity. There is at most very little 

 proof for the assertion that the specific animal poisons vary 

 in their intensity to any great degree, but at any rate such 

 variation counts for very little when compared with that 

 manifested in different individuals exposed to the influences 

 of the same epidemic, and under similar circumstances. 

 Scarlet-fever, small-pox, typhus and typhoid, diphtheria,, 

 erysipelas, syphilis, carbuncle, tetanus : how variously are 

 different individuals affected by each of these ? Not one, 

 but many volumes might be written as to the agency 

 exercised by idiosyncrasy in predisposing to, and modifying 

 disease, but I shall conclude my observations on this 

 interesting subject by quoting from Mr. Jonathan Hutchinson r , 

 who has done so much to throw light upon the influence 

 of heredity in disease, and who says : " If we fail to 

 recognise, or if we forget, the influences of idiosyncrasy, we 

 shall not only waste much time in our processes of clinical? 

 research, but we shall be in constant danger of coming to 

 wrong conclusions by declining to accept evidence as to 

 cause which is really sound, and of adopting false principles 

 in reference to treatment. In every example of a curious 

 and unexpected form of disease, our minds should, I think, 

 first ask the question, * How much of this may possibly be 

 due to the individual peculiarities of its subject ?' We are 

 often on a wrong track if we seek to make external influences 

 explain the whole. It seems to me of great practical moment 

 that the individual peculiarities of all patients should be 

 carefully studied and that they should themselves be made 

 intelligently acquainted with them. There are few of us 

 without our idiosyncrasies, and their variety is innumerable."' 



