78 Sioux City Academy of Science and Letters. 



by nearly all educated persons who have thought of 

 them. The matter of the whole vast cosmos is alive with 

 energy flashing from sun to sun. In the future I can 

 see two other theories just as closely bound together as 

 are those of matter and energy. These will be the con- 

 servation of life and the conservation of mind. I am 

 aware that this idea was hinted at by Grecian philoso- 

 phers thousands of years ago. May it not be that these 

 inseparable twins, life and mind, are, as known to us 

 in the whole organic kingdom of this world, as fixed 

 and unchangeable as are the other two, of matter and 

 energy? It will be more difficult for science to demon- 

 strate the truth of these two conservations than it was 

 to explain and show the workings of the theories of mat- 

 ter and energy which are in reach of our science, as their 

 manifestations go on in our world. But the man who 

 fixes a limit to scientific progress in knowledge by man 

 is much more sanguine in his belief than are those who 

 have studied the progress in this direction during the 

 last hundred vears. 



