On the Psycho-Analytic Concept of Identity1

In the Middle Ages the human soul was considered a kind of instrument that produces thoughts and feelings, just as a violin produces music but is not the music itself. At the dawn of the New Era, Descartes, it is true, stated that this instrument, the soul, is of a quite special type and made this statement a basic assumption of his philosophy; but the concept itself he left unchanged. Change was achieved by the English empiricists: Locke, Berkeley and Hume. They considered that the soul was not an instrument that produced thoughts and feelings, but that those thoughts (in their terminology: ideas and impressions) were the soul itself. Thus in them the soul is not more than its temporary content. But they came upon one difficulty: how do I know that my thoughts of yesterday and those of today are thoughts of the same thinking subject? This problem they called the problem of human identity. They solved it by suggesting that among my present thoughts there is memory of my thoughts of other times and that memory is exactly the same kind of 'idea' as other ideas. Thus in these authors identity is deduced from memory.

At the same time there had emerged on the Continent the philosophy of Leibnitz. In his view human identity, i.e. the fact that man feels identical with what he was in the past, is considered the most specifically human property that precedes all human functioning. Leibnitz states for instance that man can only be punished for crimes which he committed in the past by virtue of his feeling identical with what he was at the time of the deed, and that it would not occur to anybody to punish an animal for something perpetrated long ago. So in this trend of thought identity is not deduced from memory but, on the contrary, precedes memory; it is the principle that alone makes memory possible.

I have not said all this to add to my paper the traditional ornament of a historical introduction but because the views of Leibnitz and Locke just described domin