54 Heredity, Variation and Genius 



observation which unfortunately show how little 

 is really known, how much has yet to be learnt, 

 of the laws of human heredity. The sober truth 

 is that nothing so definite is known as to warrant 

 conclusions of the least practical value. It is not 

 known how it comes to pass that from the unions 

 of the germs of two ordinary human stocks the 

 remarkable variation styled genius is engendered : 

 so extraordinary an outcome from that which is 

 ordinary, something so uncommon from that which 

 is common. It is not known again why one 

 of two children of the same parents issuing from 

 the same womb, on the same bed, in the same 

 house, and reared under the same conditions, 

 grows to be a person of superior mental stature 

 while the other does not rise above mediocrity, 

 perhaps sinks below it. Nay more, although 

 knowing accurately the ancestry, it is not possible 

 so much as to foretell in a particular case whether 

 the offspring shall be long or short, male or 

 female, any more than whether it shall be fool or 

 genius. In the absence of such exact and positive 

 knowledge prescriptive rules of human breeding 

 must obviously be guesswork, despite Mr. Galton's 

 sanguine assertion that " it would be quite prac- 

 ticable to produce a highly gifted race of men 

 by judicious marriage during several successive 

 generations." 



Were the optimistic experiment made on 

 the basis of our present scanty knowledge of 

 the laws ruling in human breeding it would 



