THE ELEMENTS OF ORGANIC EVOLUTION. 77 



efforts. The effects of environment are practically rec- 

 ognised in processes of education, of agriculture, the 

 care and nurture of men and of horses and trees and 

 wheat. Evil surroundings produce evil effects. Easy 

 surroundings, reducing the stimulus to effort, tend to 

 produce organic degeneration. In larger ways response 

 to environment produces a long series of " concessions." 

 A character or condition in itself of the nature of a re- 

 sponse to outside stimulus may be called a concession. 

 Among such concessions are the skin, the eyes, the 

 brain, the sense of pain, in fact, in the ultimate analysis, 

 every organ and every function of the body. For with- 

 out environment all these would be unnecessary. Their 

 existence would be inconceivable. 



The fitness by which organisms have been perpetu- 

 ated is simply obedience or adaptation. Those which 

 survive are fitted to the conditions of life. In other 

 words, they are obedient to these conditions. Hence 

 we may define the process as one of the survival of the 

 obedient. The force which commands obedience is that 

 of the environment, and the obedience demanded is 

 that of such a reaction or relation to this environment 

 as will not obstruct the processes of life. 



Every form or phase of obedience shows itself as 



adaptation. Every adaptation is a concession to the 



actual environment on the one hand, to 

 Concessions of ^^^ j^^^ ^^ jj^^ ^^ ^j^^ ^^^^^ ^j^^ ^^^^_ 



life. , , . , . 



tion of the eye, for example, is to give 



information as to the nature of objects more or less re- 

 mote from the organism. The purpose of giving this 

 knowledge is to enable the organism to act upon it. 

 To be able to act demands that the action must be safe. 

 If the creature could not act, it would have no need for 

 such knowledge. If its acts were not in accord with 

 knowledge, the knowledge would be useless. If there 



