CHAPTER VII. 



The Parasitic Origin of Malignant Growths.* 



Some little time ago I came to the conclusion, on a priori 

 grounds, that malignant growths must be caused by para- 

 sites, and I wrote down my arguments with the intention 

 of publishing them on a suitable occasion, not knowing that 

 the theory had already been advanced. Having read the inter- 

 esting experiments of Mr. Ballance and Mr. Shattock, I am 

 led to publish my views. 



The phenomena of life fall under two main heads, the first 

 relating to the organism, the second to its environment. Let 

 us symbolize the former by the letter S, the latter by E. Now, 

 confining for the moment our attention to a unicellular or- 

 ganism, we know that if the cell and its environment be 

 properly constituted, a certain interaction takes place, and this 

 is healthy life. S + E represents a set of material conditions 

 which inevitably issue in healthy inter-action, and these 

 material conditions are the cause of life. But if either S or 

 E be improperly constituted, either no vital inter-action takes 

 place at all, which is death, or an improper vital inter-action 

 occurs, and this is disease. Wherefore disease may be defined 

 as an abnormal mode of life. These remarks apply likewise 

 to multi-cellular organisms. Every cell in such organisms is 

 surrounded by a space which constitutes its E, and the life 

 of a multicellular organism at any one moment consists- 



* This chapter is inserted here to show the principles set forth in this work 

 in actual application. It was originally intended for publication in one of the 

 medical journals, but as it only appeared there in abstract, I deem it advisable 

 to insert it here in full, and at the risk of some repetition, as the method of 

 argument followed is based upon the principles I have been endeavouring to 

 enunciate. I should add that when it was first written the parasitic theory 

 was unknown to me. 



