266 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1940 



Still others see in the modern developments and threats of warfare 

 a warning finger of the doom of civilization. I would remind these 

 doubters that evolution as we know it is built upon destruction ; that 

 the development of the whole animal kingdom rests upon destruction 

 of green plants, which biologically are formed of the same stuff as we 

 are, and that within the animal kingdom the flesh eaters have risen 

 upon the bodies of their fellow creatures. The drama of wars 

 among mankind seizes the imagination, and history books bias the 

 mind by emphasizing wars and ignoring the quiet but effective work 

 of millions of unknown citizens through the ages. But in our per- 

 spective of hundreds of millions of years these are the merest inci- 

 dents, and war or no war, the quiet progress of evolution flows through 

 life carrying the world of living things steadily but unobtrusively 

 from one step to a higher. 



In his short past man has been moving toward a higher intellec- 

 tual, spiritual, and moral standard, and the biological view would 

 be that in the immediate future (geologically speaking) that move- 

 ment will continue and that for human beings this future lies in 

 the development and perfection of social life and in the spreading of 

 the social idea to include peoples and nations as well as individuals, 

 with all the correlated advances that these imply. 



That is the short view of man's future, but what of the long view 

 of mankind upon the earth? I notice that Sir James Jeans contem- 

 plates (1929, p. 338), at any rate fancifully, the existence and prog- 

 ress of humanity until the shadow of the extinction of life upon the 

 earth falls upon the world many millions of years hence. Does our 

 vista of life support such a view? 



We must admit that any view of science about the future of hiunan- 

 ity can be only a short-range forecast; of the long-range forecast it 

 can say nothing. The reason is that science knows only the past and 

 the present, so that it can read into the future only the glorification 

 or degradation of what has already been expressed in mankind, let 

 us say better brains, better social organization, less self-seeking. 

 Yet the unfathomable characteristic of life is that it is always throw- 

 ing up something new; evolution proceeds not only by permutations 

 and combinations of the old, but by the emergence of new lines of 

 development. The physicist can foretell with accuracy the move- 

 ments of the planets, the return of eclipses and comets, but who 

 knowing only fishes could have foretold the amphibia which arose 

 from them, or knowing only the reptiles could have foretold their 

 descendants the birds and the mammals? When we leave details, in 

 the world of living things we can be wise only after the event, we 

 cannot be wise before the event. Therefore the long future of evo- 

 lution upon the earth is unknowable, so far as science is concerned. 



