4 EVOLUTION OF TO-DA Y. 



phenomena, while it is still occasionally used in its 

 earlier significance. It has come almost universally 

 to refer not to the development of the individual 

 from the egg, but to the development of the whole 

 existing order of nature from the past. In this 

 sense, too, it has a wide range. On the one hand, 

 it may mean a simple advance of one generation 

 over another in any particular. Man's rise in intelli- 

 gence during the last two thousand years is said to 

 be evolution ; or the gradual growth in the efficacy 

 of weapons of war may be called an evolution. But 

 on the other hand, the term has been stretched in its 

 meaning until it covers the origin of all things, and 

 with certain philosophers it is supposed to be a uni- 

 versal law which explains the present universe. 

 Foremost among these stand Spencer and Haeckel, 

 who believe that, starting with the existence of a 

 homogeneous nebular mass, the result by the sim- 

 plest natural laws would be a system such as we 

 now find. Spencer tells us that by the unequal 

 action of force upon this nebula, its homogeneity is 

 soon broken up, and the nebula thus becomes re- 

 solved into a number of unequal masses. By the 

 continued action of the same persistent force, the 

 masses concentrate, and the planets appear with 

 their satellites. Later, by the same process, atoms 

 of carbon unite with atoms of hydrogen, nitrogen, 

 and oxygen, and the result is protoplasm ; and thus 

 life arises spontaneously. Life now goes on develop- 

 ing, the old giving rise to new and constantly higher 

 and more complex forms, until the result is the 

 present vegetable and animal world, which has thus 



