Essays on Life 



What other main common features between 

 heredity and memory may we note besides 

 the fact that neither can exist without that 

 kind of physical continuity which we call 

 personal identity ? First, the development of 

 the embryo proceeds in an established order ; 

 so must all habitual actions based on memory. 

 Disturb the normal order and the performance 

 is arrested. The better we know " God save 

 the Queen," the less easily can we play or 

 sing it backwards. The return of memory 

 again depends on the return of ideas associated 

 with the particular thing that is remembered 

 we remember nothing but for the presence 

 of these, and when enough of these are pre- 

 sented to us we remember everything. So, if 

 the development of an embryo is due to 

 memory, we should suppose the memory of 

 the impregnate ovum to revert not to yester- 

 day, when it was in the persons of its parents, 

 but to the last occasion on which it was an 

 impregnate ovum. The return of the old 

 environment and the presence of old associa- 

 tions would at once involve recollection of 

 the course that should be next taken, and the 



same should happen throughout the whole 



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