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diseases which is inherited, but this latter can only be 

 regarded as an effect of the same causes working differently, 

 as they do in every individual producing in one a predis- 

 position, in another an insusceptibility. Regarding, then, 

 hereditary predisposition to disease as a scientific fact, and 

 bearing in mind that none of us are free from its influence 

 since it is also scientifically correct to say that every atom 

 and function of man's physical and mental nature are also 

 subject to heredity it assuredly must follow that the same 

 atoms and functions are liable to certain morbid processes 

 in consequence of the same influence, especially as diseases 

 are merely particular conditions of the living body, new 

 phases of its vital manifestations, whether of the nature of 

 functional derangements, or of organic or textural degeneracy. 

 To sum up : man, physiologically and psychologically, to 

 the minutest detail, being subject to the law of heredity, it 

 must follow that he has also inherited certain predispositions 

 to disease which, in the presence of certain exciting causes, 

 will develop into active morbid processes : in a word, man 

 is alike subject to heredity in health and in disease. 



In addition to hereditary predisposition, we find that the 

 individuality of man consists also of temperament, idiosyn- 

 crasy, and diathesis. How do these latter affect the pre- 

 dispositions to disease in individuals ? The temperaments are 

 the sanguine, nervous, lymphatic, and bilious. The sanguine 

 predisposes to diseases characterised by the rapidity of the 

 inflammatory process, and predisposes its possessors to 

 acute affections, which develop themselves regularly and 

 completely, defervesce rapidly, and generally with well- 

 marked symptoms of crisis. The nervous temperament 

 predisposes to disorders of the nervous system, convulsive 

 diseases, various congestions and haemorrhages, hepatic and 



