Pleasure, Pain, and the Circular Reaction 123 



replaced by the plasticity necessary for learning by con- 

 sciousness. So it seems to me that the evidence points to 

 some inverse ratio between the importance of conscious- 

 ness as factor in development and the need of the inher- 

 itance of acquired characters as factor in evolution. This 

 presumptive argument may be supplemented, I think, with 

 positive refutations of the considerations which Professor 

 Cope, Mr. Romanes, and others present for the view that 

 the transmission of functions acquired through conscious- 

 ness requires the Lamarckian factor.^ 



§ 2. Pleasure, Pain, and the Circular Reaction 



There is one omission in Professor James' excellent 

 division of our topic into its members — an omission whose 

 importance may justify my bringing up a phase of the 

 general question to which I think too much importance 

 can hardly be attached. It is, in biological phrase, the 

 ontogenetic question, the examination of the development 

 of consciousness in the individual, with a view to interpret- 

 ing the results for light upon the method of evolution. 



Professor Cope's emphasis on consciousness rests here, 

 and it is well placed. In the life history of the organ- 

 ism we have the problem of development actually solved 

 before us in detail. The biologist recognizes this in his 

 emphasis on embryology and also in some degree in his 

 paleontology. But the psychologist has not realized the 

 weapon he has both for biological and for psychological use 

 in the mental development of the child. Moreover, the 

 biologist no less than the psychologist must needs resort 

 to this field of investigation if he would finally settle the 



1 See the preceding papers. 



