8 The Common Sense of the Evolution Question 



is the principle of continuity^ or the constancy of the universe 

 — what is now, ever has been and shall remain. 



Nothing New Under the Sun 



Millions of gallons of water pass over Niagara Falls 

 every week. Yet the Falls look about the same as they did 

 several years ago when you first saw them. They remain the 

 same year after year, and, for all we know, century after 

 century. The oceans and lakes and the everlasting hills give 

 us a hint of eternity. The stars that blink silently in the 

 sky have seen hundreds of generations come and go, but their 

 positions, their risings and their settings remain fixed and 

 steadfast. 



The materials of the earth remain the same. Man may 

 pile rock upon rock to build him tombs or temples: but he 

 creates nothing new. He merely rearranges what his hands 

 have found. While some of the combinations that human 

 ingenuity has set up may amuse us or startle us, we know 

 that they are only new combinations of what has al- 

 ready existed. Every house, for example, is but a variation 

 on a very ancient theme. Shooting off a sixteen-inch shell 

 is but a variation of the game which David played with 

 Goliath. 



It is common sense to recognize that, in spite of con- 

 stant change, today is the daughter of yesterday. In human 

 experience events do not jump out at us from a vacuum. If 

 the world is always changing, it is still always the world. 

 The very changes show a certain constancy — day and night; 

 season after season; generation, maturity and death. If it is 

 common sense to recognize the facts of change, it is also 

 common sense to recognize the enduring things of life and 

 of the universe, the uniformities and constancies by which 

 alone we can guide ourselves in the midst of change. It is 

 these enduring uniformities that science seeks to discover. 

 And that, too, is a part of the study of evolution, for here 

 we seek to answer not only the question ** What changes 



