446 POPULAR SCIENCE MONTHLY. 



tions it has not been wholly unprofitable. It has enabled lis to trace 

 a number of conditions which, even if they cannot always be described 

 as factors of the genius constitution, clearly appear among the in- 

 fluences highly favorable to its development. Such a condition seems 

 to be the great reproductive activity of the parents, the child destined to 

 attain intellectual eminence in many cases alone surviving. The fact 

 of being either the youngest or the eldest child is a condition favor- 

 able for subsequent intellectual eminence; and I may add that I could 

 refer to numerous recent instances of large families, in which the 

 eldest and the youngest, but no other members, have attained intellec- 

 tual distinction. We have further seen that there is a tendency for 

 children who develop genius to be of feeble health, or otherwise dis- 

 abled, during the period of physical development. It is easy to see the 

 significance of this influence which by its unfavorable effects on the de- 

 velopment of the limbs — an effect not exerted on the head which may 

 thus remain relatively large — leaves an unusual surplus of energy to 

 be used in other directions; at the same time the child, who is thus 

 deprived of the ordinary occupations of childhood, is thrown back on to 

 more solitary and more intellectual pursuits. The clumsiness and 

 other muscular incoordinations which we have found to be prevalent — 

 while there is good reason to believe that they are of congenital origin 

 — cooperate to the same end. Again, it is easy to see how the shock of 

 contact with a strange and novel environment, which we have proved to 

 be so frequent, acts as a most powerful stimulant to the nascent in- 

 tellectual aptitudes. It is possible to take a number of other common 

 peculiarities in the course of the development of genius and to show 

 how they either serve to inhibit the growth of genius along unfruitful 

 lines or to further it along fruitful lines. 



Such an investigation as the present is far from enabling us to 

 state definitely all the determining factors of genius, or even all the 

 conditions required for its development. It suggests that they are 

 really very numerous and that genius is the happy result of a combina- 

 tion of many concomitant circumstances, though some of the prenatal 

 group of circumstances must remain largely outside our ken. We are 

 entitled to believe that the factors of genius include the nature of the 

 various stocks meeting together in the individual and the manner of 

 their combination, the avocations of the parents, the circumstances at- 

 tending conception, pregnancy and birth, the early environment and all 

 the manifold influences to which the child is subjected from infancy 

 to youth. The precise weight and value of these manifold circum- 

 stances in the production of genius it must be left to later investiga- 

 tors to determine. 



