Another distinction is here suggested between the memory of a sensation and the memory of an idea. The complex idea, which needs to be associated with a mere simple idea, to make it memory, is not the same in the two cases. There is a specific difference. The self which is at the antecedent end of the associated train, (in the case of sensation,) is the sentient self; that is, seeing or hearing; the self at the antecedent end of the associated train, (in the case of ideas,) is not the sentient self, but the conceptive self, self having an idea. But myself percipient, and my self imagining or conceiving, are two very different states of consciousness: of course the ideas of these states of consciousness, or these states revived by association, are very different ideas. The simplest of all cases of memory is that of a sensation immediately past. I have one sensation, and another sensation; call them A and B; and I recognise them as successive. Every man has experience of the fact, and is familiar with it. But not every man can tell what it involves. When a sensation ceases, it is as completely gone, as if it had never existed.[93] It is, in a certain sense, {337} revived again in its idea. But that idea must be called into existence by something with which it is associated. In my two sensations, supposed above, the one antecedent, the other consequent, how do I recognise the succession; if the first is gone, before the coming of the second? It is evident that it must be by memory. And how by memory? The preceding developments seem to make the process clear. The consciousness of the present moment calls up the idea of the consciousness of the preceding moment. The consciousness of the present moment is not absolutely simple; for, whether I have a sensation or idea, the idea of what I call Myself is always inseparably combined with it. The consciousness, then, of the second of the two moments in the case supposed, is the sensation combined with the idea of Myself, which compound I call "Myself Sentient." This "Self Sentient," in other words sensation B, combined with the idea of self, calls up the idea of sensation A combined with the idea of self. This we call MEMORY; and, there being no intermediate link, _immediate_ MEMORY. Suppose that, instead of two sensations, there had been three, A, B, C. In order {338} to remember A, it is necessary to step over B. The consciousness of the third moment, namely, "sensation C, united with the idea of self," calls up the idea of "sensation A, united with the idea of self," and along with this the intermediate state of consciousness, "B, with the constant concomitant self." If the intermediate state, B, were not included, the sensation A would appear to have immediately preceded sensation C, and the memory would be inaccurate.