72 Unconscious Memory 



conscious world ; and as we know nothing of this but what 

 investigation into the laws of matter teach us — as, in fact, 

 for purely experimental purposes, " matter " and the 

 " unconscious " must be one and the same thing — so the 

 physiologist has a full right to denote memory as, in the 

 wider sense of the word, a function of brain substance, 

 whose results, it is true, fall, as regards one part of them, 

 into the domain of consciousness, while another and not 

 less essential part escapes unperceived as purely material 

 processes. 



The perception of a body in space is a very complicated 

 process. I see suddenly before me, for example, a white 

 ball. This has the effect of conveying to me more than 

 a mere sensation of whiteness. I deduce the spherical 

 character of the ball from the gradations of light and 

 shade upon its surface. I form a correct appreciation of 

 its distance from my eye, and hence again I deduce an 

 inference as to the size of the ball. What an expenditure 

 of sensations, ideas, and inferences is found to be necessary 

 before all this can be brought about ; yet the production 

 of a correct perception of the ball was the work only of a 

 few seconds, and I was unconscious of the individual 

 processes by means of which it was effected, the result as 

 a whole being alone present in my consciousness. 



The nerve substance preserves faithfully the memorj' 

 of habitual actions.^ Perceptions which were once long 

 and difficult, requiring constant and conscious attention, 

 come to reproduce themselves in transient and abridged 

 guise, without such duration and intensity that each 

 link has to pass over the threshold of our consciousness. 



We have chains of material nerve processes to which 

 eventually a link becomes attached that is attended with 

 conscious perception. This is sufficiently established from ■ 



' See quotation from Bonnet, p. 54 of this volume. By " pre- 

 serving the memory of habitual actions " Professor Hering probably 

 means, retains for a long while and repeats motion of a certain 

 character when such motion has been once communicated to it. 



