xix IS NATURE CRUEL? 383 



whatever into the blood of a really healthy person is to 

 create a danger far greater than the disease itself. 



On the general principles of the present argument there 

 can be nothing in nature which is not useful, and, in a broad 

 sense, essential to the whole scheme of the life -world. On 

 this principle the purpose and use of all parasitic diseases, 

 including those caused by pathogenic germs, is to seize upon 

 the less adapted and less healthy individuals those which 

 are slowly dying and no longer of value in the preservation 

 of the species, and therefore to a certain extent injurious 

 to the race by requiring food and occupying space needed 

 by the more fit. Their life is thus shortened, and a linger- 

 ing and unenjoyable existence more speedily terminated. 

 One recent writer seems to hold this view, as shown by the 

 following passage : 



" Before it was perceived that disease is an undisputable battle- 

 field of the true Darwinian struggle for existence, the tremendous 

 part which it takes in ridding the earth of weaklings and causing 

 the survival of health, was all credited to the environment and its 

 dead physical forces." 1 



But in this interesting article the writer elsewhere uses 

 language implying that even the healthy require rendering 

 " immune " against all zymotic diseases. It is that idea 

 which I protest against as a libel on nature and on the 

 Ruler of the Universe ; and in its practice as constituting a 

 crime of equal gravity with vivisection itself. 



It will be said that quite healthy persons die of these 

 diseases, but that cannot be proved ; and the absolutely 

 universal fact that it is among those living under unhealthy 

 conditions in our towns, and cities, and villages, that suffer 

 most from these diseases is strongly against the truth of the 

 statement. No doubt savage races often suffer dreadfully 

 from these diseases ; but savages are no more universally 

 healthy than the more civilised, though it is usually a 

 different kind of unhealthiness. The only doctrine on this 

 matter worthy of an evolutionist, or of a believer in God, is 

 that health of body and of mind are the only natural safe- 

 guards against disease ; and that securing the conditions for 



1 Parasitism and Natural Selection, by R. G. Eccles, M.D., Brooklyn, N.Y., 

 U.S.A. 



