EUGENICS 137 



port, Goddard and Kosanoff, which they interpret as evidence that orig- 

 inal imbecility is due to the absence of a single determiner, and that 

 an originally neurotic, unstable mental organization is explainable 

 almost as simply. It is with regret that I must assure you that these 

 observations are susceptible of a very different interpretation. Much as 

 I should like to believe that these burdens on man's nature are each 

 carried in heredity in a single package, which selective breeding can 

 shuffle off in a generation or so, I can not. A eugenics that assumes that 

 intellect, morality, sanity and energy are so many single niches in the 

 germs which selective breeding can, by simple transfers, permanently 

 fill, is, I fear, doomed to disappointment and reaction. I dare to believe 

 that the time will come when a human being idiotic by germinal defect 

 will be extinct like the dinosaur — a subject for curious fiction and for 

 the paleontology of human nature; but I have no hope that such a 

 change can be made with the ease with which we can change short 

 peas to tall, curly-haired guinea pigs to sleek, or plain blossoms to 

 mottled ones. 



There is another fundamental question whose answer is needed for 

 the most economical selective breeding of human nature, a question 

 which time permits me only to mention, not to describe clearly. Stated 

 as a series of questions, it is this : Do the germs which a man produces 

 — his potential halves of offspring — represent a collection peculiar to 

 him, or only a collection peculiar to some line, or strain, or stock, or 

 variety, of mankind of which he is one exemplar ? 



Suppose a hundred men and a hundred women to exist, each with 

 identical germinal constitutions, so that, say, in every case one tenth 

 of the germs (or ova) would be of quality 5; one fifth, of quality 6; 

 two fifths, of quality 7 ; one fifth, of quality 8 ; and one tenth, of quality 

 9. Suppose that they mated and had five hundred offspring. Suppose 

 that the best fifty of this second generation married exclusively among 

 themselves ; and similarly for the worst fifty. Would the offspring of 

 these two groups differ, the children of the best fifty being superior to 

 the children of the worst fifty? Or would this third generation revert 

 absolutely to the condition of the grandparental stock whence they all 

 came ; and be alike, regardless of the great difference in their parentage ? 



Does the selection of a superior man pay because his superiority is, 

 in and of itself, a symptom of probable excellence in his germs ; or only 

 because his superiority is a symptom that he is probably of a superior 

 " line " or strain ? 



That the second answer of each pair may be the true one, is a natural, 

 though not, I think, an inevitable, inference from the work of Johanssen, 

 Jennings and others. They have found selective breeding within any 

 one pure line futile, save when some peculiar and rare variations have 

 taken place within it. Their work is of very great importance and 



TOL. Lxxxm.— 10. 



