THE CONCEPTUAL WORLD 39 



repetitions of the same stimuli was that the later ones 

 became added to the earlier ones, so that the state of 

 consciousness produced by, or which was concomitant 

 with, these external stimuli was a different state in 

 each case. 



This is the duration of the intelligently acting 

 animal : it is not merely memory, but memory and the 

 accumulation of all its past modes of responding to 

 changes in its environment, whether these modes of 

 response were conscious ones (as in the case of an 

 intelligently performed or " learned " action), or un- 

 conscious ones (as, for instance, in the case of the ac- 

 quirement of immunity by an animal which had become 

 able to resist disease) . It is not merely the experience 

 of the individual organism, but also all the experience 

 of those things which were done or experienced by 

 the ancestry of the organism, and which were trans- 

 mitted by heredity to the progeny. Motor habits are 

 formed, so that much the same series of muscular 

 actions are carried out when a stimulus formerly 

 experienced is again experienced. Pure memory 

 remains, so that the images of past things and actions 

 somehow persist in our consciousness. Physical 

 analogy suggests that these images are inscribed on the 

 substance of the brain or are stored away in some 

 manner ; but, apart from the incredible difficulty of 

 imagining a mechanism competent for this purpose, it 

 is obvious that we thus apply to the investigation of 

 our consciousness (which is an intensive multiplicity), 

 the concept of extension which can only apply in all 

 its strictness to the things outside ourselves on which 

 we are able to act. All these motor habits, functional 

 reactions, and memory images are our duration or 

 accumulated experience. The motor habits and those 

 functional habitual reactions of other parts of the body 



