In order to complete the theory, we must consider some other facts and psychical phenomena, both normal and abnormal, so as to ascertain whether these are not due to the same cause, as far as respects their intrinsic forms; namely, the belief in the reality of images seen in dreams, as well as in those which appear in illusions, in normal hallucinations of the senses, and in those which are abnormal, in ecstasy, in delirium, in madness, in idiocy, and dementia. In all these mental conditions, we ascribe a body and material existence to images which for various causes appear to be really presented to our senses.
If we are able to show that all such appearances are believed to have a real existence in virtue of the same law and faculty of perception which generated myth in its earliest manifestation, we shall have succeeded in establishing a common genesis for all these various psychical phenomena, thus affording no contemptible contribution to psychology in general, and to the science of human thought.
To dream is not merely a normal act of man, but, as it appears from many witnesses, it is common to all animals. In dreams the ordinary laws of time and space are strangely modified, and images of all kinds appear, sometimes confusedly, sometimes in a rational order, often in accordance with the laws of association, while the voluntary exercise of thought may be said to be dormant. This is, speaking generally, the condition and nature of dreams, which we must presently consider adequately with more subtle and exact analysis.
Before we trace the cause of the apparent reality of these images, and the laws which govern it, let us consider man in his waking condition, so as to ascertain at once the likeness and the difference between these two states. We must first inquire whether the waking is absolutely distinct from the dreaming state as far as the appearance of the images, their nature, and mode of action are concerned. It has been observed by many psychologists and physiologists that in the waking state, when images do not arise from the immediate presence of objects, or are not directed by the will to a definite aim, they appear, group themselves, and disperse by the immediate association of ideas, and the measurements of time and space are modified just as they are in dreams. These observations are correct, and the phenomena may be verified by every one for himself.
In this waking state, which really resembles that of dreams, only the analogy of form has been perceived; the ideas of the objects present to the mind have resembled those of images seen in dreams, but they have continued to be mere ideas, presented to the imagination, whereas in dreams the things seen have been supposed to have a real existence. In this respect the analysis is partly true and partly false; it is not, as we shall see, perfect and exact.
It sometimes happens, owing to special circumstances and conditions of mind, or to peculiar temperaments, that the ideas of things do not remain as mere thoughts in the thinker's mind, but that they become so intense that they are for the moment held to be real, precisely as in a dream.
I do not here speak of abnormal or pathological conditions, or of extraordinary phenomena, but of a normal and common condition. If there is any novelty in the assertion, it is owing to a want of observation and reflection, and to not attempting to trace the real nature of the phenomena in which we take part, and which occur every day. The habitual inaccuracy of observation has led to the use of many proverbs and aphorisms in the interpretation of things which have been transmitted from one generation to another, and are now accepted as indubitable axioms. These are to be found in every branch of knowledge, and we have an instance in the popular and scientific aphorism that in dreams images appear to be real, and that in the waking state they always continue to be mere thoughts and ideas.
This is not the fact, since, putting illusions and hallucinations out of the question, thoughts and ideas sometimes assume the character and nature of real objects, just as they do in dreams. This fact constitutes the link and gradual assimilation of the two states, since in no series of phenomena natura facit saltum.
When, for instance, as often happens, we abandon ourselves to a train of thought, and our perception of surrounding objects is weakened by inattention, we become as it were unconscious, and are only intent on the thoughts and ideas which move us. Since no definite object constrains the will to rule and guide these thoughts and ideas, that condition of mind is established which we have shown to be identical in form with the act of dreaming, for in this case also thoughts and ideas have their origin in association alone. In this condition a phenomenon peculiar to dreams may also occur which may be termed the suggestive impulse; a sound or some sudden sensation produces an immediate transformation of the image itself, and a new dream arises in conformity with the nature of the new impression. Every one must, consciously or unconsciously, have experienced such a phenomenon, and this special characteristic of dreams may also take place in the waking condition which I have described. I myself can bear witness to this fact, and will mention one among several instances: I was once reading inattentively, seated at my ease in a lounging chair, and my thoughts took quite another direction, wandering vaguely from one thing to another. All at once some people entered an adjoining room talking together; I heard what they said indistinctly, but the word Florence reached my ears, and I soon imagined myself to be in that city, and going on from one association to another I continued for some time to see again the places, monuments, and people I had known there. Yet I was fully awake, and from time to time I brushed the flies from my face and glanced at the clock on the chimney-piece, since I had to go out at three o'clock.
It appears from this fact, which will be confirmed by many of my readers, that some waking states resemble those of dreams in form, and moreover they are sometimes even alike in substance. Ideas and thoughts in the conditions just indicated may not only be latent, active, combined, or transformed by suggestive impulses, but ideas are represented by images in such vivid relief that, until the observer recollects himself, they are seen and felt by him with the same sense of reality as in a dream. This mental transformation is however so habitual, that the implicit conviction of being really awake, does not allow us to observe what the actual nature of the phenomenon is, since there is an immediate transition from an implicit perception of the image as real to the habitual form of simple thought, without distinguishing the difference between these two states of consciousness. Any one who has long practised himself in the observation of such distinctions will, however, be able to understand the psychical process and to estimate its value.