It is true, as a study of the coconscious would show, that such phenomena of anesthesia and unrecognized perceptions are dependent upon a dissociation of consciousness and upon coconscious perception. But this is a matter of mechanism with which we are not now concerned. The point simply is that subconscious perceptions which never entered the awareness of the personal consciousness may be conserved.
I will cite one more observation, one in which the reproduction was through secondary translation, as we shall see later that it belongs to a class which enables us to determine the nature of conservation.
B. C. A., actuated by curiosity, looked into a crystal and saw there some printed words which had no meaning for her whatever and awakened no memory of any previous experience. It was afterward found that these words represented a cablegram message which she unconsciously overheard while it was being transmitted over the telephone to the telegraph office by my secretary in the next room. She had no recollection of having heard the words, as she was absorbed in reading a book at the time. The correctness of the visual reproduction is shown, not only by automatic writing which remembered and recorded the whole experience, but also by comparison with the original cablegram.
Again, in other experiments there appear, in the crystal, visions rich in detail of persons whom she does not remember having seen, although it can be proved that she actually has seen them.
The reproduction of subconscious perceptions and forgotten knowledge in dreams, visions, hypnosis, trance states, by automatic writing, etc., is interesting apart from the theory of memory. Facts of this kind offer a rational interpretation of many well-authenticated phenomena exploited in spiritistic literature. Much of the surprising information given by planchette, table rapping, and similar devices commonly employed by mediums, depends upon the translation of forgotten dormant experiences into manifestations of this sort. In clinical medicine, too, we can often learn, through reproductions obtained by special methods of investigation, the origin of obsessions and other ideas which otherwise are unintelligible.
Dreams and somnambulisms.—Many people remember their dreams poorly or not at all, and, in the latter case, are under the belief that they do not dream. But often circumstantial evidence, such as talking in their sleep, shows that they do dream. Now, though ordinarily they cannot remember the dreams, by changing the waking state to an hypnotic one, or through the device of crystal visions or automatic writing, it is possible in some people to reproduce the whole dream. Amnesia for dreams, therefore, cannot be taken as evidence that they do not occur, and forgotten dream consciousness is subject to the same principles of conservation and reproduction as the experiences of waking life. Thus in B. C. A. dreams totally forgotten on awakening are easily recovered in hypnosis and in crystal visions.[[30]] In the case of M——l, which I cited to you a little while ago, the forgotten dream in which he lived over again the original episode which led to the development of his hysterical condition and which when repeated in the dream induced each successive attack, was easily recovered in hypnosis. The same was true of the forgotten dreams of Mrs. H. and Miss B.
The reproduction of nocturnal somnambulistic acts and the ideas which occupied the content of consciousness of the somnambulist can be effected in the same manner. I have quite a collection of observation of this kind. In the study of visions,[[31]] to which I have already referred, may be found the observation where Miss B., looking into a crystal, sees herself walking in her sleep and hiding some money under a tablecloth and books lying on the table. The money (which was supposed to have been lost) was found where it was seen in the vision.
In my notebook are the records of numerous artificial hallucinations of this kind which reproduce sleep-walking acts of B. C. A. To cite one instance: in the crystal she sees herself arise from her bed, turn on the lights, descend the stairs, enter one of the lower rooms, sit by the fire in deep, pensive reflection, then get up and dance merrily as her somnambulistic mood changes. Presently, as the cinematograph-like picture unfolds itself in the crystal, she sees herself go to the writing table, write two letters, ascend the stairs, dropping one letter on the way,[[32]] reënter her room, open a glove box, place the remaining letter under the gloves, and finally put out the lights and get into bed when, with the advent of sleep, the vision ends. In the vision the changing expression of her face displays each successive mood. In hypnosis also the scene is remembered and then even the thoughts which accompanied each act of the somnambulist are described. Here again, then, we have evidence that even forgotten dreams and somnambulistic thoughts are not lost but under certain special conditions can be revived in one mode or another.
II. Forgotten Experiences of Artificial and Pathological States
The experiences that I have thus far cited in evidence of the principle of the conservation of dormant experiences that cannot be voluntarily recalled have been drawn almost entirely from normal everyday life. We now come to a series of facts which are very important in that they show that what is true of the experiences of everyday life is also true of those of artificial and pathological states of which the normal personal consciousness has no cognizance. These facts are also vital for the comprehension of post-hypnotic phenomena, of amnesia, multiple personality, and allied dissociated states. Let us consider some of the states from the point of view of conservation.