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exposed to the effects of a chill : some will be found to 

 suffer no injurious consequences, but one will develop an 

 attack of pneumonia, another of bronchitis, another apoplexy, 

 another nephritis, another jaundice, another gout, another 

 acute rheumatism, another gastro-intestinal derangement, 

 and so on according to the individual predisposition of each 

 person. So also, let us imagine several individuals equally 

 exposed to the influence of some morbid-poison, as of 

 cholera ; similarly we shall find that, owing to relative 

 insusceptibility, some of them will pass unscathed through 

 the ordeal ; others will develop a severe or fatal attack of 

 cholera ; others will probably only surfer from diarrhoeaic 

 symptoms, with gastro-intestinal disturbance ; and, again, 

 others from vomiting, cramps, and characteristic evacuations. 

 In analysing a man's inherited individuality we have seen 

 that it depends upon natural variability, and the transmission 

 of ancestral, parental, and uterine influences ; also that 

 these inherited qualities may be subdivided into tempera- 

 ment, idiosyncrasy, hereditary predisposition, and diathesis. 

 How do these latter affect the predisposition to disease in 

 individuals ? Temperament, as I have already stated, has 

 nothing to do with disease in itself, being a part of the 

 inherited physical and mental constitution of every individual^ 

 irrespective of any morbid tendencies ; but that it becomes 

 an important factor in predisposing to disease will be seen 

 from the following facts. It should be here remembered that 

 the temperaments, sanguine, nervous, lymphatic, bilious, 

 however well-defined, are seldom or never seen in their 

 ideally perfect state, for as individuals differ from each other 

 in every respect, what is true of the whole must also be true 

 of its parts ; therefore, as a matter of fact, every individual 

 presents an intermingling of temperaments in different 



