Animal Life and Intelligence. 



of the individuals, or more frequently of a majority among 

 a cultivated minority. In any case, we have seen that 

 metakineses are and must be an individual matter. For 

 each individual there is a separate ideal world. 



Through certain activities, notably language spoken or 

 written, men can symbolize to each other the ideas that are 

 taking metakinetic shape in their own minds. All-im- 

 portant, however, as is this power of intercommunication 

 by means of language, it does not a whit alter the fact that 

 the idea and its environment have to work out their rela- 

 tions to each other separately in each individual mind. 

 My neighbour may symbolize, through language, his ideas 

 in such a form that similar ideas may be called up in my 

 mind ; but it is there that they have to make good their 

 claim for acceptance in the environment of the system of 

 ideas among which they are introduced. 



Now, what is the guiding principle of the evolution and 

 development of ideas in the world of their metakinetic 

 environment ? Is there any principle analogous to that of 

 elimination which we have seen to be of such high impor- 

 tance in organic evolution ? I believe that there is. An 

 idea is accepted or rejected according to its congruity or 

 incongruity with the system of ideas among which it is 

 introduced. The process has, perhaps, closer analogy with 

 elimination than with selection, inasmuch as it would 

 seem to proceed by the rejection of the incongruous, leaving 

 both the congruous and the neutral. An idea or hypothesis 

 may be accepted, at any rate provisionally, so long as it is 

 not in contradiction to the theories and beliefs already 

 existing in the mind. 



It may, however, be objected that this view is at variance 

 with the familiar observation that there are many excellent 

 people who hold and maintain theories which are exceed- 

 ingly incongruous, which seem, indeed, to us mutually 

 antagonistic. Yes, to us. Brought into the environment 

 of our system of ideas, one or other of these antagonistic 

 views would be eliminated through incongruity. Not so, 

 however, with those who hold both. Amid the environ- 



