CONTROL OF HEREDITY: EUGENICS 399 



longer. Barring great secular changes, catas- 

 trophes or cataclysms, which cannot be fore- 

 seen or provided against, man controls his 

 own destiny on this planet. 



It is a curious fact that in prescientific times 

 the instability of nature especially appealed to 

 men. How often in the past have men looked 

 forward to a "speedy end of the world"! It 

 may well have seemed to our ancestors a use- 

 less thing to take any thought for the morrow 

 if very soon the heavens are to be rolled up as 

 a parchment and the elements dissolved in fer- 

 vent heat; it would be folly to plan for future 

 ages if the time is at hand when the angel 

 shall stand with one foot on the sea and the 

 other on land and declare that time shall be 

 no more. But science has taught us something 

 of the wonderful stability of nature, something 

 of the immensity of past time and of future 

 ages, something of the eternity of natural pro- 

 cesses. Compared with this infinite stability 

 and eternity of nature what are our little sys- 

 tems and customs! Our years and centuries 

 fall like grains of sand into this abyss of time. 

 Our individual lives are like drops of water in 



