Memory proper, or secondary memory as it might be styled, is the knowledge of a former state of mind after it has already once dropped from consciousness; or rather it is the knowledge of an event, or fact, of which meantime we have not been thinking, with the additional consciousness that we have thought or experienced it before.
The first element which such a knowledge involves would seem to be the revival in the mind of an image or copy of the original event.[575] And it is an assumption made by many writers[576] that the revival of an image is all that is needed to constitute the memory of the original occurrence. But such a revival is obviously not a memory, whatever else it may be; it is simply a duplicate, a second event, having absolutely no connection with the first event except that it happens to resemble it. The clock strikes to-day; it struck yesterday; and may strike a million times ere it wears out. The rain pours through the gutter this week; it did so last week; and will do so in sæcula sæculorum. But does the present clock-stroke become aware of the past ones, or the present stream recollect the past stream, because they repeat and resemble them? Assuredly not. And let it not be said that this is because clock-strokes and gutters are physical and not psychical objects; for psychical objects (sensations for example) simply recurring in successive editions will remember each other on that account no more than clock-strokes do. No memory is involved in the mere fact of recurrence. The successive editions of a feeling are so many independent events, each snug in its own skin. Yesterday's feeling is dead and buried; and the presence of to-day's is no reason why it should resuscitate. A farther condition is required before the present image can be held to stand for a past original.
That condition is that the fact imaged be expressly referred to the past, thought as in the past. But how can we think a thing as in the past, except by thinking of the past together with the thing, and of the relation of the two? And how can we think of the past? In the chapter on Time-perception we have seen that our intuitive or immediate consciousness of pastness hardly carries us more than a few seconds backward of the present instant of time. Remoter dates are conceived, not perceived; known symbolically by names, such as 'last week,' '1850;' or thought of by events which happened in them, as the year in which we attended such a school, or met with such a loss.—So that if we wish to think of a particular past epoch, we must think of a name or other symbol, or else of certain concrete events, associated therewithal. Both must be thought of, to think the past epoch adequately. And to 'refer' any special fact to the past epoch is to think that fact with the names and events which characterize its date, to think it, in short, with a lot of contiguous associates.
But even this would not be memory. Memory requires more than mere dating of a fact in the past. It must be dated in my past. In other words, I must think that I directly experienced its occurrence. It must have that 'warmth and intimacy' which were so often spoken of in the chapter on the Self, as characterizing all experiences 'appropriated' by the thinker as his own.
A general feeling of the past direction in time, then, a particular date conceived as lying along that direction, and I defined by its name or phenomenal contents, an event imagined as located therein, and owned as part of my experience,—such are the elements of every act of memory.
It follows that what we began by calling the 'image,' or 'copy,' of the fact in the mind, is really not there at all in that simple shape, as a separate 'idea.' Or at least, if it be there as a separate idea, no memory will go with it. What memory goes with is, on the contrary, a very complex representation, that of the fact to be recalled plus its associates, the whole forming one 'object' (as explained on page 275, Chapter IX), known in one integral pulse of consciousness (as set forth on pp. 276 ff.) and demanding probably a vastly more intricate brain-process than that on which any simple sensorial image depends.
Most psychologists have given a perfectly clear analysis of the phenomenon we describe. Christian Wolff, for example, writes:
"Suppose you have seen Mevius in the temple, but now afresh in Titus' house. I say you recognize Mevius, that is, are conscious of having seen him before because, although now you perceive him with your senses along with Titus' house, your imagination produces an image of him along with one of the temple, and of the acts of your own mind reflecting on Mevius in the temple. Hence the idea of Mevius which is reproduced in sense is contained in another series of perceptions than that which formerly contained it, and this difference is the reason why we are conscious of having had it before.... For whilst now you see Mevius in the house of Titus, your imagination places him in the temple, and renders you conscious of the state of mind which you found in yourself when you beheld him there. By this you know that you have seen him before, that is, you recognize him. But you recognize him because his idea is now contained in another series of perceptions from that in which you first saw him."[577]
Similarly James Mill writes:
"In my remembrance of George III., addressing the two houses of parliament, there is, first of all, the mere idea, or simple apprehension, the conception, as it is sometimes called, of the objects. There is combined with this, to make it memory, my idea of my having seen and heard those objects. And this combination is so close that it is not in my power to separate them. I cannot have the idea of George III.: his person and attitude, the paper he held in his hand, the sound of his voice while reading from it; without having the other idea along with it, that of my having been a witness of the scene.... If this explanation of the case in which we remember sensations is understood, the explanation of the case in which we remember ideas cannot occasion much of difficulty. I have a lively recollection of Polyphemus's cave, and the actions of Ulysses and the Cyclops, as described by Homer. In this recollection there is, first of all, the ideas, or simple conceptions of the objects and acts; and along with these ideas, and so closely combined as not to be separable, the idea of my having formerly had those same ideas. And this idea of my having formerly had those ideas is a very complicated idea; including the idea of myself of the present moment remembering, and that of myself of the past moment conceiving; and the whole series of the states of consciousness, which intervened between myself remembering, and myself conceiving."[578]
Memory is then the feeling of belief in a peculiar complex object; but all the elements of this object may be known to other states of belief; nor is there in the particular combination of them as they appear in memory anything so peculiar as to lead us to oppose the latter to other sorts of thought as something altogether sui generis, needing a special faculty to account for it. When later we come to our chapter on Belief we shall see that any represented object which is connected either mediately or immediately with our present sensations or emotional activities tends to be believed in as a reality. The sense of a peculiar active relation in it to ourselves is what gives to an object the characteristic quality of reality, and a merely imagined past event differs from a recollected one only in the absence of this peculiar-feeling relation. The electric current, so to speak, between it and our present self does not close. But in their other determinations the re-recollected past and the imaginary past may be much the same. In other words, there is nothing unique in the object of memory, and no special faculty is needed to account for its formation. It is a synthesis of parts thought of as related together, perception, imagination, comparison and reasoning being analogous syntheses of parts into complex objects. The objects of any of these faculties may awaken belief or fail to awaken it; the object of memory is only an object imagined in the past (usually very completely imagined there) to which the emotion of belief adheres.