The Fitness of Ideas 261 



minds, either one's own or some one's else. So the en- 

 vironment must be the persons about the thinker. They 

 constitute his environment ; they give him conditions to 

 react upon ; they are the control factor in his higher selective 

 thinking, just as the world of things is the control factor 

 in his life of sense perception. I know that it is through 

 their life of action — mainly indeed, the speech functions 

 — that he realizes their thought, and it is through his life 

 of action that he reacts upon their thought and exhibits 

 his ; but even in knowledge of the external world of signs, 

 expressions, etc., we have to say that movement must be 

 reduced to some form of thought in order to be organized 

 in our knowledge. And as soon as we get out of the 

 sphere of knowledge of the world of things, and ask how 

 knowledge can proceed without the selective control of 

 physical fact upon movement, we have to say that if selec- 

 tion is to have reference to any environment at all it must 

 have reference to an environment of thinking. Apart from 

 theory, however, the social life is as a matter of fact the 

 environment of our thinking ; in the recent book already 

 referred to,^ there is cited much evidence to show that the 

 child organizes his thoughts with constant reference to the 

 control which the social environment enforces. 



So we have found that each group of thought-variations, 

 to be candidates for selection, must be projected from a 

 platform of acquired knowledge, represented on the motor 

 side by certain elements in the attention complex which 

 give the sense of familiarity, class identity, general truth, 

 or vague universality. This is the platform of systematic 

 determination through the attention. Now, why not stop 

 here? Because when a new thing comes, this does not 



^ Social and Ethical Interpretations. 



