SEMON. WARD. KIGNANO 343 



This was an elaborate treatment of the question from the 

 materialistic point of view, the main assumption of Semon's 

 theory being that the action of a stimulus upon the organism 

 leaves a more or less permanent material trace or " engramm," 

 of such a nature as to modify the subsequent action of the 

 organism. 



Applied to the explanation of heredity and development, 

 Semon's theory comes to very much the same as Weismann's, 

 with engramms substituted for determinants, but it has the 

 great advantage of allowing for the transmission of acquired 

 characters. The application of the concept of stimulus is 

 valuable and suggestive, but it seems to us that the memory 

 theory of heredity can be properly utilised only by adopting a 

 frankly Lamarckian and vitalistic standpoint, and this stand- 

 point Semon expressly combats. As Ward 1 points out in his 

 illuminating lecture on heredity and memory " Records or 

 memoranda alone are not memory, for they presuppose it. 

 They may consist of physical traces, but memory, even when 

 called ' unconscious,' suggests mind ; for, as we have seen, 

 the automatic character implied by this term 'unconscious' 

 presupposes foregone experience. . . . The mnemic theory 

 then, if it is to be worth anything, seems to me clearly to 

 require not merely physical records or ' engrams,' but living 

 experience or tradition. The mnemic theory will work for 

 those who can accept a monadistic or pampsychist interpre- 

 tation of the beings that make up the world, who believe 

 with Spinoza and Leibniz that 'all individual things are 

 animated albeit in divers degree' " (pp. 55-6). 



Perhaps the best and most ingenious treatment of 

 memory and heredity from a physical standpoint is that 

 offered by E. Rignano in his book, Sur la transmissi- 

 bilite des caracfcres acquis;- Rignano seeks to construct 

 a physico-chemical " model " which will explain both heredity 

 and memory. 



His system, which is based more firmly upon the facts 

 of experimental embryology than Semon's, postulates the 

 existence of "specific nervous accumulators." The essential 



1 Heredity and Memory, Cambridge, 1913. 



' Paris, 1906. Also in Italian and German. Eng. trans, by B. C. H. 

 Harvey, Chicago, 1911. 



Z 



