The servility, the state of fear of the subconscious, the source of neurosis, in its relation to the master hypnotizer is well brought out in the mechanism of hypnotic and post-hypnotic hallucinations.

Before we proceed with our discussion it may be well to give an analysis, however brief, of the normal percept, of the abnormal percept or hallucination, and then compare them with hypnotic and post-hypnotic hallucinations. The understanding of perception, normal and abnormal, is, in fact, at the basis of normal and abnormal psychology.

We may begin with the percept and its elements. In looking at the vase before me I see its beautiful tints, its rounded shape, its heavy pedestal with its rough curves, its solidity, weight, brittleness, and other experiences which go to make up the perception of the vase. The visual elements are given directly by the visual perceptive experience; but whence come the seemingly direct experiences of weight, heaviness, roughness, smoothness, and others of the like kind? They are evidently derived from other senses. The whole perceptive experience is of a visual character. We take in the whole with our eye. In the organic structure of the percept then, besides the experiences directly given by the stimulated sense-organ, there are other experiences, sensory in character, indirectly given, and coming from other sense organs which are not directly stimulated.

The percept is a complicated dynamic product, and its elementary processes are never derived from one isolated domain of sensory experience. The activities of all the sensory domains co-operate in the total result of an apparently simple percept. Along with sensory processes directly stimulated, a mass of other sensory processes becomes organized and helps to contribute to the total result. The direct sensory elements are termed by me primary sensory elements; the indirectly given experiences are termed secondary sensory elements. The secondary sensory elements may be figuratively said to cluster round the primary sensory elements as their nucleus.

The whole perceptual experience is tinged by the character of the primary elements which constitute the guiding nucleus, so to say. Thus, where the primary sensory elements are visual, the whole mass, no matter from what domain the sensory experiences are derived, appears under the form of the visual sense, and the percept is a visual percept. While the primary sensory elements form, so to say, the dynamic center of the total perceptual experience, the secondary sensory elements mainly constitute its content. Both primary and secondary elements are sensory and are induced peripherally; the primary directly, the secondary indirectly. The percept then is sensory and is constituted by primary sensory elements, or primary sensations, and by secondary sensory elements, or secondary sensations.

The character of the secondary sensory elements stands out clear and independent in the phenomena of synaesthesia, of secondary sensations. In the phenomena of synaesthesia we have a sensation of one sense organ followed, without an intermediary direct stimulation, by a sensation coming from another sense organ. Thus, when a sensation of light instead of giving rise to a subsequent idea gives rise to a sensation of sound, for instance, we have the phenomenon of secondary sensation. Here the secondary sensations stand out free and distinct, but they are really always present in our ordinary perceptive experiences as bound up secondary sensory elements, as secondary sensations grouped round primary sensations.

When the phenomena of synaesthesia were first brought to the notice of the scientific world, they were regarded as abnormal and exceptional, and only present in special pathological cases. Soon, however, their field became widened, and they were found not only in the insane and degenerate, but in many persons otherwise perfectly normal. We find now that we must further widen the field of secondary sensory elements, and instead of regarding them as a freak of nature existing under highly artificial conditions, we must put them at the very foundation of the process of perception.

Secondary sensations are at the basis of perception. We have become so accustomed to them that we simply disregard them. When, however, the conditions change, when the secondary sensations stand out by themselves, isolated from the primary nuclear elements with which they are usually organically synthesized into a whole, into a percept, when they become dissociated, it is only then that we become conscious of them directly and declare them as abnormal.

Secondary sensations are always present in every act of perception; in fact, they form the main content of our perceptual activity, only we are not conscious of them, and it requires a special analysis to reveal them. Secondary sensations per se are not something abnormal—just as hydrogen present in the water we drink or the oxygen present in the air we breathe are not newly created elements,—it only requires an analysis to discover them. If there be any abnormality about secondary sensations, it is not in the elements themselves, but rather in the fact of their dissociation from the primary nuclear elements.

When the secondary sensory elements come to the foreground and stand out clearly in consciousness, a full-fledged hallucination arises. In the phenomena of synaesthesia we have hallucinations in the simplest form, inasmuch as only isolated secondary sensory elements dissociated from their active primary central elements stand out in the foreground of consciousness. This very simplification, however, of hallucinations reveals their inner character. The most complex hallucinations are only complex compounds, so to say, of secondary sensory elements. Hallucinations are not anything mysterious, different from what we find in the normal ordinary processes of perception; they are of the same character and have the same elements in their constitution as those of perception. Both hallucinations and percepts have the same secondary as well as primary elements. The difference between hallucinations and percepts is only one of relationship, of rearrangement of elements, primary and secondary. When secondary sensory elements become under conditions of dissociation dynamically active in the focus of consciousness we have hallucinations.

From this standpoint we can well understand why a hallucination, like a percept, has all the attributes of external reality. A hallucination is not any more mysterious and wonderful than a percept is. We do not recognize the humdrum percept, when it appears in the guise of a hallucination, and we regard it as some strange visitant coming from a central, or from some supersensory universe. Hallucinations, like percepts, are constituted of primary and especially of secondary sensory elements, and like percepts, hallucinations too are induced peripherally.

How is it with suggested[13] or hypnotic hallucinations? Do we find in hypnotic or suggested hallucinations, as in the case of hallucinations in general, the requisite primary and secondary sensory elements directly and indirectly induced? Binet makes an attempt to establish a peripheral stimulus in the case of hypnotic hallucinations, claiming that there is a point de repÉre, a kind of a peg, on which the hypnotic hallucination is hung. It is questionable whether Binet himself continued to maintain this position. However the case may be, this position is hardly tenable when confronted with facts. Hypnotic hallucinations may develop without any peg and prop.

Furthermore, granted even that now and then such a peg could be discovered, and that the alleged hypnotic hallucination develops more easily when such a peg is furnished, still the fact remains that even in such cases the peg is altogether insignificant, that it is altogether out of proportion and relation to the suggested hallucination, and that on the same peg all kinds of hallucinations can be hung, and that finally it can be fully dispensed with. All this would go to show that the peg, as such, is of no consequence, and is really more of the nature of an emphatic suggestion for the development of the alleged hypnotic or post-hypnotic hallucinations.

The arbitrariness of the hypnotic hallucinations, showing that the whole thing is simply a matter of representations, or of what the patient happens to think at that particular moment, is well brought out in the following experiments: Mr. F. is put into a hypnotic state, and a post-hypnotic suggestion is given to him that he shall see a watch. The eyeball is then displaced, the watch is also displaced; now when the eyeball returns to its normal condition we should expect that the hallucinatory watch would return to its former place; but no, the watch is not perceived in its previous place,—it appears in a displaced position. The hallucinatory watch could thus be displaced any distance from its original position. The patient evidently did not see anything, but simply supplied from his stock of knowledge as to how a seen watch would appear under such conditions, and he omitted to observe the fact that with the normal position of the eye the watch should once more return to its former position. Such inconsistencies are often found in hypnosis.

More intelligent and better informed patients would reason out the matter differently, and would give different results. If the subject knows of contrast colors and if a color is suggested to him he will without fail see such contrast colors. If his eyes have been fixed on some hallucinatory color, such as red, for instance, he will even give you a detailed account of the green he sees, but if he does not know anything of the effects of contrast colors no amount of fixation on hallucinatory colors will bring out the least contrast effects. The reason is the patient does not know anything about it and cannot think of it.

We tried to mix by suggestion different hallucinatory colors, and as long as he knew nothing of the real results his replies were uniformly wrong; no sooner did he find out what the right mixture should be than he gave correct results. The hypnotic subject really does not perceive anything; he tells what he believes the master wants him to see under the given conditions. The subconscious fear instinct makes the hypnotized subject obey and please the hypnotizer, as the dog obeys his master.