Physiology of Central Nervous System 73 



only on simple mechanical arrangements. In the last analysis, 

 then, we would arrive at molecules and atoms endowed with 

 mental qualities. We can dispose of this view by the mere fact 

 that the phenomena of embryological development and of 

 organization in general show a degree of purposefulness which 

 may even surpass that of any reflex or instinctive or conscious 

 act. And yet we do not consider the phenomena of develop- 

 ment to be dependent upon consciousness. 



On the other hand, physiologists who have appreciated the 

 untenable character of such metaphysical speculations have 

 held that the only alternative is to drop the search for the 

 mechanisms underlying consciousness and study exclusively the 

 results of operations on the brain. This would be throwing 

 out the ^^heat with the chaff. The mistake made by meta- 

 physicians is not that they devote themselves to fundamental 

 problems, but that they employ the wrong methods of investi- 

 gation and substitute a play on words for an explanation by 

 means of facts. If brain physiology gives up its fundamental 

 problem, namely, the discovery of those elementary processes 

 which make consciousness possible, it abandons its best possi- 

 bilities. But to obtain results, the errors of the metaphysician 

 must be avoided and explanations must rest upon facts, not 

 words. The method should be the same for animal psj'chology 

 that it is for brain physiology. It should consist in the right 

 understanding of the fundamental process which recurs in 

 all psychic phenomena as the elemental component. This 

 process, according to my opinion, is the activity of the associative 

 rnemory, or of association. Consciousness is only a metaphysical 

 term for phenomena which are determined by associative 

 memory. By associative memory I mean that mechanism by 

 which a stimulus brings about not only the effects which its 

 nature and the specific structure of the irritable organ call for, 

 but by which it brings about also the effects of other stimuli 

 which formerly acted upon the organism almost or quite 



