232 THE HISTOEY OF CT.EATION. 



because it is the chief and most comprehensive among them. 

 It may be briefly explained in the following proposition: 

 " All organic individuals become unequal to one another in 

 the course of their life by adaptation to different conditions 

 of life, although the individuals of one and the same species 

 remain mostly very much ahke." A certain inequality of 

 organic individuals, as we have seen, was already to be 

 assumed in virtue of the law of individual (indirect) adapt- 

 ation. But, beyond this, the original inequality of indivi- 

 duals is afterwards increased by the fact that every individual, 

 during its own independent life, subjects and adapts itself 

 to its own peculiar conditions of existence. All different 

 individuals of every species, however like they may be in 

 their first stages of hfe, become in the further course of 

 their existence less like to one another. Thev deviate 

 from one another in more or less important peculiari- 

 ties, and this is a natural consequence of the different condi- 

 tions under which the individuals live. There are no two 

 single individuals of any species which can complete their 

 life under exactly the same external circumstances. The 

 vital conditions of nutrition, of moisture, air, light ; further, 

 the vital conditions of society, the inter-relations with 

 surrounding individuals of the same or other species, are 

 different in every individual being ; and this difference 

 first affects the functions, and later changes the form of 

 every individual organism. K the children of a human 

 family show, even at the beginning, certain individual 

 inequalities which we may consider as the consequence 

 of individual (indirect) adaptation, they will appear 

 still more different at a later period of life, when each 

 child has passed through different experiences, and has 



