CONSERVATIVE DESIGN OF ORGANIC DISEASE. 167 



at least during the first few days of life, but the liability continues, 

 though in a gradually-decreasing ratio, until physiological develop- 

 ment is complete. Breeders of stock know very well the difficulty of 

 rearing the young; and even in wild animals that live in a perfectly 

 natural state, untrammeled by domestication, a good proportion of 

 new-born individuals perish in early life. Gardeners and agricultu- 

 rists drop more seeds in a place (of corn " in a hill," for instance) than 

 they intend shall remain as plants, knowing that in the earlier stages 

 of growth many of the " seedlings " will die ; and, if more shall remain 

 than is advisable, they are afterward "thinned" by hand. Surely 

 every mother of a family knows the difficulty of rearing children, and 

 our "bills of mortality" sufficiently attest the immense /"aia^zYy at- 

 tending physiological development in the hitman family . 



Now, while in each of the instances I have cited the causes and 

 mode of death are similar to or at least analogous with each other, it is 

 only in the case of our own species that, generally speaking, we say 

 death has been caused hy disease. In the young chick, the wild ani- 

 mal, and the seedling plant, we are content to say they die because 

 they are young, or " tender." The truth is, that death has been due, 

 in each case, to an arrest of, or interference with, the quite normal pro- 

 cess of physiological developm.ent, and to put this conception to a fur- 

 ther test we may begin still a little earlier in life by studying embry- 

 onic development. In the case of oviparous animals, for example, we 

 know many of the eggs never come to perfection ; the young embryos 

 they contain die during incubation. And while the pathologist, if he 

 were to delve with his microscope into the secret physiology and pa- 

 thology of the growing embryo, might find difierent membranes and 

 organs fatally afiected (congested or inflamed) according to the dififer- 

 ent stages of development at which the mortal disturbance took place, 

 it would seem very odd, in case it should happen to be the rudimentary 

 lungs of the growing embryo that were found specially congested, if 

 he should say the eg^ had been " attacked " with pneumonia (inflam- 

 mation of the lungs) ; or, if he should find the heart or intestines con- 

 gested, how queer it would sound to say the egg had died from an at- 

 tack of carditis (inflammation of the heart), or enteritis (inflammation 

 of the intestines) ! yet these so-called diseases are just as much causes 

 of death in the egg as in the child after it is born. 



The relevancy of the facts mentioned to the question at issue the 

 bearing of the argument is this: oi'ganisms undergoing physiological 

 evolution, and those in which pathological evolution is going on, are 

 alike liable to be fatally aflfected by certain disturbing causes that in- 

 terfere with the typical progress of development in each ; hence the 

 great mortality incident to childhood and early life is strictly analo- 

 gous with the mortality attending organic diseases in the adult. 



This analogy may now be further sustained by considering what 

 these disturbing causes really are ; and here I may premise they will 



