338 EVOLUTION OF TO-DAY. 



have been discovered, and probably others remain 

 yet unthpught of. The reproduction of organic 

 beings is the result of two somewhat contradictory 

 laws, Heredity and Variation. In accordance with 

 the first, species tend to produce offspring precisely 

 like themselves. In accordance with the second, 

 they tend to produce offspring differing from them- 

 selves. These two laws, and the forces governing 

 them, must be the factors which have produced 

 whatsoever evolution there has been. Naturalists 

 are now at work endeavoring to reach a better un- 

 derstanding of these laws, and out of their work we 

 may hope for further knowledge. At present, then, 

 while it is well to admit with the scientist that or- 

 ganic evolution is probably true, and that it may or 

 may not include man, it is also evident that the 

 complete explanation of the theory has not been 

 reached. Above all, the investigations have not 

 brought scientists much nearer to the real signifi- 

 cance of life itself, which, like all other first princi- 

 ples, becomes the more inexplicable the more it is 

 studied. 



