THE QUESTION OF FORM PERCEPTION 333 



figure i. Now rotate the book in a plane perpendicular to the 

 lines of vision. The visual experience certainly has changed; 

 and the more naive the observer tries to be, the more it seems 

 as though even the " geometrical form" of the book has changed tool 

 This is the state of affairs, I believe, in the animal and the 

 young child. 7 The reader need not think that he is invited to 

 construct a situation which is beyond the powers of animals 

 and children. Quite the contrary. He is only asked to neglect 

 his own developed and sophisticated knowledge of the details 

 of his environment (which it is important to' remember the 

 animal lacks) and attempt to reinstate that which may be 

 genetically simple. 



One further point deserves ' comment. The discrimination of 

 two "complexes" is often easier than that of two "simples." 

 What the experimenter regards as simple, i.e., as readily at- 

 tended to, may prove very difficult to discriminate. The fault 

 lies in the confusion of logical and genetic simplicity. Logically 

 a pattern, in that it involves an interrelation of elements, is 

 more complex than a single form; but genetically the form is 

 more complex in that it is the later development. 



Although I have limited the discussion so far to the question 

 of form discrimination, the same comments apply mutatis mu- 

 tandum to the problem of size discrimination, although here I 

 should be willing to grant that a priori the dependence upon 

 the background of projection might be less than was the case 

 with form. All experiments upon form and size discrimination 

 that I remember having seen have neglected this factor. Con- 

 trols must be used which introduce differently shaped tunnels. 

 It is only after such experimentation that the present hypo- 

 thesis — with animals and young children, "form" discrimination 

 is always pattern discrimination — can be proved or disproved. 8 



7 The subjection of children to tests with apparatus similar to that described 

 by the authors above cited is something that should be undertaken before a truly 

 comparative statement can be given. 



8 The 'writer has presented the above in theoretical form because all of his spare 

 time is taken in experimentation along a different line. The indications are that 

 this will be true for an indefinite period. In the interim some other investigator 

 may see fit to carry out experiments as suggested above. 



