106 PATHOLOGY 



human medicine and for a long time the vast resources of general 

 biology remained practically unused in the study of disease. On 

 the other hand, owing to lack of appreciation of the fact that dis- 

 ease is a phenomenon of life, in other words, owing to the unnatural 

 separation of the biologic study of disease from general biology, 

 the subject of disease has rather repelled the average student of 

 biology, who therefore seems to have neglected to utilize fully the 

 approaches offered by pathology to a better knowledge of the 

 phenomena of life. 



In view of the extent to which man has busied himself with the 

 study of all forms of animal life in all accessible parts of the world, 

 is it not rather strange and an evidence of lack of coordination 

 that the occurrence of cancer throughout the whole vertebrate 

 kingdom should have been made out definitely only during the 

 last year? Yet this demonstration by the Cancer Research Fund 

 in London, and the further demonstration that cancer has the same 

 fundamental characters as in man when it occurs in fish, reptile, 

 and bird, renders it extremely improbable that either climate or 

 diet of man has anything to do with the direct causation of cancer, 

 thus putting an end to much needless speculation and materially 

 narrowing the scope of a most important inquiry. 



Pathological Processes in Evolution 



In some quarters disease has been regarded merely as an expres- 

 sion of inferiority and weakness, and as part at least of the means 

 by which inexorable nature carries out the verdict of extermina- 

 tion. Parasitism for instance has been designated as a weapon to 

 eliminate those who fall below a certain standard. Consideration 

 of the nature of disease from this point of view gives to disease 

 merely a negative evolutional significance, as it would cause no 

 new and better qualities in the descendency. Closer examination 

 would tend to show, however, that processes of disease may have 

 a different significance of a more positive nature in evolution. There 

 are numerous simple as well as complex physiological processes 

 which, when set in motion by abnormal conditions, appear to be 

 of advantage not only to the individual but also to the species. 

 As examples of adaptive processes at first sight of more special 

 individual advantage may be mentioned regeneration, hypertro- 

 phy, the interesting adaptations to new and strange conditions 

 of which bones and vessels are capable, certain phases of throm- 

 bosis, and even atrophy, which has been described as the faculty 

 of an organ to adapt itself to conditions of diminished nutrition, 

 thus circumventing necrosis, a faculty of great advantage when 

 the period of dyninished food-supply is only temporary. No one 



