464 THE WORLD MACHINE 



might suffice greatly to change our ideas of the future. The 

 discovery of radium and the cathode radiations, emanations, of 

 the pressure of radiation, and the like, to all of which reference 

 has repeatedly been made, may very distinctly alter our ideas as 

 to the age of the earth, of the sun as well. In the course of 

 three or four centuries, three or four other discoveries may 

 come of yet more vital import. 



There is, however, one central fact which, for aught we may 

 now see, may never be modified and from which we can never 

 escape. The cosmic machine runs on. We die. La vie est brfoe, 

 _^a vie est court. It seems fairly incontestable that life had a 

 beginning upon the earth, and, what is of much deeper import, 

 there was a time in the history of the earth when it bore no 

 human race. So far as we can see, that which has a beginning 

 must also have an end. When the candle of the sun has been 

 burnt to its socket, the cycle of evolution which produced our 

 race will have turned downwards and backwards, returning to 

 the bathybii and lichens from which we sprang. 



The history of the earth does not suggest a high importance 

 for the individual human life. We may roughly estimate the 

 period of man at from two to five hundred thousand years, 

 perchance a million let us say, roughly, ten to thirty thousand 

 generations. It does not seem probable that the number of 

 human beings on earth has varied very greatly in ten or twenty 

 thousand years, perhaps not in fifty thousand. At present the 

 number is about fifteen hundred millions in American notation, 

 a billion and a half. The personnel of this number is changed 

 on the average once in twenty-five or thirty years. 



It is easy to see that the aggregate number of human beings 

 who have ever lived upon earth runs into hundreds, it may 

 be thousands, of billions. The lives of the vast majority of these 

 were of as much consequence to human history as the spawn of 

 fishes or the larvae of flies. It is considerations of this sort which 

 make it difficult to understand at times the ardour with which 

 men pursue the shows and baubles of this world. 



The individual life is of little consequence to the race. The 

 aggregate life of the race seems of little consequence to the 

 earth. Billions upon billions of coral polyps may materially alter 

 the surface of the globe. Probably their work will be of more 

 consequence, will have effected greater changes in terrestrial 

 conditions, than all that will ever be effected by man himself. 



