Introduction to Hering's Lecture 55 



personality than that it was inseparable from the idea 

 that the various phases of our existence should have flowed 

 one out of the other, " in what we see as a continuous, 

 though it may be at times a very troubled, stream " ; ^ 

 but I maintained that the identity between two successive 

 generations was of essentially the same kind as that 

 existing between an infant and an octogenarian. I thus 

 left personal identity unexplained, though insisting that 

 it was the key to two apparently distinct sets of pheno- 

 mena, the one of which had been hitherto considered in- 

 compatible with our ideas concerning it. Professor Hering 

 insists on this too, but he gives us farther insight into 

 what personal identity is, and explains how it is that the 

 phenomena of heredity are phenomena also of personal 

 identity. 



He implies, though in the short space at his command 

 he has hardly said so in express terms, that personal 

 identity as we commonly think of it — that is to say, as 

 confined to the single life of the individual — consists in 

 the uninterruptedness of a sufficient number of vibrations, 

 which have been communicated from molecule to molecule 

 of the nerve fibres, and which go on communicating each 

 one of them its ow'n peculiar characteristic elements to the 

 new matter which we introduce into the body by way of 

 nutrition. These vibrations may be so gentle as to be 

 imperceptible for years together ; but they are there, and 

 may become perceived if they receive accession through 

 the running into them of a wave going the same way as 

 themselves, which w'ave has been set up in the ether by 

 exterior objects and has been communicated to the organs 

 of sense. 



As these pages are on the point of leaving my hands, I 

 see the following remarkable passage in Mind for the 

 current month, and introduce it parenthetically here : — 



" I followed the sluggish current of hyaline material 

 issuing from globules of most primitive living substance. 



^ Life and Habit, p. 97. 



