io THE LESSON OF EVOLUTION 



their way clearly. So they called themselves Agnostics, 

 thinking that no well-established beliefs on theological 

 questions were possible to the impartial investigator. 

 If this had been correct, it would have been a fatal 

 objection to the claim, which was at the same time 

 being made, that science should be included in general 

 education. Fortunately, broader and more sensible 

 views have prevailed, and it is no longer considered 

 necessary that a scientific man should he an Agnostic. 



AN OUTLINE OF EVOLUTION 



Let me now give you an outline of this theory, which 

 has wrought such a momentous change. 



The idea of evolution originated with the Greeks, 

 but only as a speculation which led to nothing ; and 

 its scientific history may be said to commence in the 

 early part of the last century, when the practically 

 new theory of the origin of species by gradual develop- 

 ment was proposed by Lamarck. This theory was at 

 first discredited for lack of evidence ; but it was 

 developed and demonstrated by C. Darwin in the 

 middle of the century. About the same time it was 

 pointed out by Lord Kelvin that not only was the sun 

 cooling, but that all kinds of energy, when converted 

 into heat, lost a portion by radiation into space, and 

 that this process must go on until the whole Universe 

 was of a uniform temperature. So that, although the 

 amount of energy in the Universe remains unalterable, 

 it will, by redistribution, be brought into the potential 

 state, and thus, when every possible action is counter- 

 balanced by other actions, energy will practically 

 disappear. 



