It seems that this stage fixed in the mind of the animal the idea of 

 treating an object to adapt it for an action that the animal was trying to 

 perform with its help. 



Up through this stage of the study, the elements of the object were 

 clearly manifest to the chimpanzee; but in ensuing experiments the features 

 of the implement were progressively obscured. 



4. The chimpanzee was provided with a long, thin, rectangular plate. 

 In this case the material given was not structurally divided into a ready 

 implement and elements that hindered its use. Now it was necessary for the 

 animal to break the object: this it did in a variety of experiments, until 

 one of the resulting fragments suggested the form of the original rod-shaped 

 implement. 



5. In the next experiment a circular disc of the same sort of wood was 

 provided: thus, nothing was manifest of the form of the necessary imple- 

 ment. The animal was required to transform the disc into certain param- 

 eters, not on the basis of any indications on the disc but solely on the basis 

 of information about them fixed in the mind of the ape. The chimpanzee 

 proved equal to this task. 



6. Before breaking the disc the chimpanzee turned it so that the grain 

 lines of the wood ran away from its body. Hence, it was subsequently given 

 discs with imitation grains drawn at right angles to the true grain. At first 

 the chimpanzee began to operate according to the illusory grain; finding 

 the disc difficult to break, it changed the direction of its actions and was 

 successful. 



7. The disguise was made more complete: grooves were carved on the 

 disc at right angles to the grain of the wood. Both surfaces of the wood 

 were then covered in thick paper, with the grooves forming a clearly dis- 

 cernible relief; furthermore, black lines were drawn between the furrows 

 perpendicular to the grain. Again the illusory grain misled the chimpanzee. 

 After repeated trials and errors it changed the direction and had success, 

 assisted by using its teeth to make a number of consecutive dents along 

 the true grain. 



Khroustov concluded that "active transformation of material having a 

 preliminary neutral form, despite its false outer appearances, into an im- 

 plement with definite parameters, is a fully attainable stage of activity 

 for a chimpanzee" (ibid., p. 506). In Khroustov's opinion, this is the level 

 of implemental activity characteristic of the australopithecines. "Its coming 

 into being signifies not the appearance of the human principle but a high 



^ 122 



