Chapter 5 - Page 2

because we remember having grown our limbs in this way, and having had these instincts in past generations when we were in the persons of our forefathers--each individual life adding a small (but so small, in any one lifetime, as to be hardly appreciable) amount of new experience to the general store of memory; that we have thus got into certain habits which we can now rarely break; and that we do much of what we do unconsciously on the same principle as that (whatever it is) on which we do all other habitual actions, with the greater ease and unconsciousness the more often we repeat them. Not only is the main idea the same, but I was surprised to find how often Professor Hering and I had taken the same illustrations with which to point our meaning.

Nevertheless, we have each of us left undealt with some points which the other has treated of. Professor Hering, for example, goes into the question of what memory is, and this I did not venture to do. I confined myself to saying that whatever memory was, heredity was also. Professor Hering adds that memory is due to vibrations of the molecules of the nerve fibres, which under certain circumstances recur, and bring about a corresponding recurrence of visible action.

This approaches closely to the theory concerning the physics of memory which has been most generally adopted since the time of Bonnet, who wrote as follows:-

"The soul never has a new sensation but by the inter position of the senses. This sensation has been originally attached to the motion of certain fibres. Its reproduction or recollection by the senses will then be likewise connected with these same fibres." . . . [54a]

And again:-

"It appeared to me that since this memory is connected with the body, it must depend upon some change which must happen to the primitive state of the sensible fibres by the action of objects. I have, therefore, admitted as probable that the state of the fibres on which an object has acted is not precisely the same after this action as it was before I have conjectured that the sensible fibres experience more or less durable modifications, which constitute the physics of memory and recollection." [54b]

Professor Hering comes near to endorsing this view, and uses it for the purpose of explaining personal identity. This, at least, is what he does in fact, though perhaps hardly in words. I did not say more upon the essence of 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" [55] 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