52 



SCIENCE 



[N. S. Vol. XXXVII. No. 941 



gence, though doubtless an "unlimited 

 microscopist" could find differences be- 

 tween the trained and the untrained brain. 

 The brains of Beethoven, Gauss and Cu- 

 vier, although unusually large, have been 

 matched in size and visible complexity by 

 the brains of unknown and lanlearned per- 

 sons — persons who were richly endowed by 

 nature, but who had never learned to use 

 their talents. In all men the capacity for 

 intellectual development is probably much 

 greater than the actuality. The parable of 

 the talents expresses a profound biological 

 truth: men differ in hereditary endow- 

 ments, one receives ten talents and another 

 receives but one ; but the used talent in- 

 creases many fold, the unused remains un- 

 changed and undeveloped. Happy is he 

 who is compelled to use his talents; thrice 

 happy he who has learned how to 

 compel himself! "We shall not live to 

 see the day when human inheritance is 

 greatly improved, though that time will 

 doubtless come, but in the meantime we 

 may console ourselves by the thought that 

 we have many half -used talents, many 

 latent capacities, and although we may not 

 be able to add to our inheritance new terri- 

 tory, we may greatly improve that which 

 we have. 



I have once or twice in this address re- 

 ferred to eugenics in a way which was 

 intended to be facetious, but I would not 

 wish to be understood as attempting to 

 disparage that infant industry. Undoubt- 

 edly it represents an important application 

 of biological discoveries to human welfare ; 

 but it seems to me that it can not wisely go 

 farther at this time than to attempt to 

 eliminate from reproduction the most unfit 

 members of society. Giving advice regard- 

 ing matrimony is proverbially a hazardous 

 performance, and it is not much safer for 

 the biologist than for othei's. With a more 

 complete knowledge with regard to the in- 



heritance of human defects than we now 

 possess, at least in many instances, it will 

 probably be possible to give such advice 

 wisely; but apart from certain bodily pe- 

 culiarities, he would be a bold prophet who 

 would undertake to predict the type of 

 personality which might be expected in the 

 children of a given union. Some very un- 

 promising stocks have brought forth won- 

 derful products. Could any one have pre- 

 dicted Abraham Lincoln from a study of 

 his ancestry? Observe I say predict, and 

 not explain after his appearance. Can any 

 one now predict from what kind of ances- 

 tral combinations the great scholars, states- 

 men, men of affairs of the next generation 

 will come? Could the capacities and ca- 

 reers of the members of this society — those 

 who were born outside of Boston or Phila- 

 delphia — have been predicted? The time 

 may come when it will be possible to pre- 

 dict what the chances are that the children 

 of given parents will inherit more or less 

 than average intellectual capacity, but since 

 germinal potentiality is transformed into 

 intellectual ability only as the result of 

 development, such a prediction could not 

 be extended to the latter unless the environ- 

 ment as well as the heredity were known. 

 Society can safely eliminate its worst ele- 

 ments from reproduction, but it can not 

 wisely go farther than that at present. 



My distinguished predecessor in this 

 office, in his striking address before this 

 society one year ago, pointed out as one of 

 the great tragedies of life the almost infi- 

 nite slaughter of potential personalities in 

 the form of germ cells which never develop. 

 A more dreadful, though less universal, 

 tragedy is the loss of real personalities who 

 have all the native endowments of genius 

 and leadership, but who for lack of proper 

 environmental stimuli have remained un- 

 developed and unknown; the "mute, in- 

 glorious Miltons ' ' of the world ; the Cffisars, 



