This work would be incomplete, if I did not carefully examine fraud and errors of observation. The first should always be considered as possible. Errors of observation are even more numerous than fraud, and their sources are manifold. We should study them, learn their causes, and suspect them until the contrary has been proved.

I. FRAUD

Fraud can be conscious, unconscious, or mixed. I have no need to say how frequent the first is, especially with paid mediums. Spiritistic reviews, notably the Revue Spirite, Revue Morale et Scientifique du Spiritisme, Light, Psychische Studien, give many examples of fraud discovered by spiritists themselves. Unconscious fraud is no less common than conscious fraud; as for the third, mixed fraud, this is also very often observed.

Conscious fraud.—(a) Raps. Nothing is easier to imitate. I have indicated the diverse ways of reproducing them artificially: gliding the finger or nail along the top of the table, with or without the help of resin; rapping with the feet; gliding the foot or dress—especially silk dresses—against the legs of table, etc. These diverse movements imitate feeble raps to perfection, if they be slowly made. For that reason I have always refused to consider raps as convincing when produced with any contact whatever. Consequently I exclude raps produced on the floor from those phenomena which have determined my conviction. Certain persons seem to be able to move their tendons at will, even making a considerable noise in that way. I observed this with a medical student who, by resting his elbow on the table, produced very sonorous raps; but the movement of his arm was easily seen. I know another person who could crack his joints at will.

The play of the knee-joint has been especially incriminated by Mrs. Sidgwick in her article ‘The Physical Phenomena of Spiritualism’ (Proceedings of the S.P.R. xiii. 45). She recalls to mind the interpretations given by Drs. Lee, Flint, and Coventry, who observed Mrs. Kane and Mrs. Underhill, two of the famous Fox sisters. Mrs. Sidgwick experimented with the third sister, Mrs. Jencken, and accepted the explanation of the American doctors. For them, the double raps were produced by a rapid movement of dislocation and readjustment of the knee. By placing in such a position as to render that voluntary dislocation impossible, e.g. by making the medium sit down with outstretched legs and heels resting on a soft cushion, no raps were forthcoming. It is possible that the explanation of the American doctors may be true concerning the case examined by them. In those which I have studied, it is certainly not acceptable. I have obtained raps on a table without any kind of contact whatsoever. I have obtained them on the floor, by placing the medium in positions which excluded the play of articulation. The kind of fraud in question was not therefore in operation. I have even made some mediums sit on my knees when raps were forthcoming; I then made sure the raps were produced on the table, and that the latter was not touched. My conclusion as to the reality of the phenomenon of raps is the result of nearly two hundred observations.

In obscurity, the means of cheating are unimaginable. I saw a young medium, who had succeeded in concealing a stick, simulate raps on the ceiling with it. I have known two others hit the table with their fists, kick it with their feet, etc. Everything is possible in darkness, and with certain confiding observers.

(b) Parakinesis, or abnormal movements of objects with contact. I have often said that all movements with contact—except certain levitations which are, however, difficult to observe with precision—are worthless. I have indicated the chief ways of simulating levitations, either by the hands, the feet or the knees. I will not revert to this.

These methods are difficult in full light, but when the experimenters are placed in such a position as to be unable to keep a reciprocal watch over the feet, the second method is still easily brought into play.

(c) Telekinesis.—Fraud is more difficult to perpetrate here. A connecting link of some kind or other would be required to move objects possessing a certain weight and bulk. I look upon this phenomenon as most convincing, when it is obtained in full light; in obscurity, it is to a certain extent unverifiable.

(d) Luminous phenomena are easily simulated; phosphorescent oil and certain sulphides give excellent imitations of hands and forms. I have seen a photograph taken by magnesian light in a seance for materialisation. The medium, by way of imitating a materialised garment of some kind, had wound a white cloth around his neck, and moreover wore a false beard. Those present at this seance will not admit they were cheated. One of the sitters, a friend of mine, one familiar with psychical matters, but too honest himself to suspect fraud in others, did not think my judgment in this case was correct. It was necessary to have it confirmed by the celebrated Papus!

As for the phenomenon of attouchements, this is of all phenomena the most easily simulated in obscurity.

Every one knows the rÔle played by dolls, disguises and confederates in seances for materialisation. The trickster’s imagination is of inconceivable fertility. The recent Rothe trial gives us a fresh example of this.

(e) Motor and sensory automatisms can be imitated with extreme facility, and their efficacious control is impossible. A careful analysis of the messages is necessary in order to appreciate their value. On the other hand, well-observed premonitions are of immense importance.

From the preceding, we see that all psychical phenomena can be simulated; this does not mean that every psychical phenomenon is simulated. Those who wish to explain away everything by fraud make as great a mistake, as those who trustingly accept everything without control.

There is an important general observation to be made concerning the phenomena I am treating in this book. It is of historical order, but nevertheless it gives a much wider signification to these facts than is usually accorded them. Many writers, Janet among them, imagine that spiritistic phenomena, as they call them, date from the celebrated events of Rochester, about the year 1847, where the Fox sisters were the objects of diverse manifestations. But in reality these facts date much further back. One of the best observed cases is the one spoken of by Dr. Kerner in his book Die Seherin von Prevorst, which has been translated by Dr. Dusart into French, probably from Mrs. Crowe’s English translation. Kerner observed raps and movements without contact from the year 1827, when he had Madame Hauff staying in his house.

Phenomena of the same kind are to be met with in accounts of haunted houses. There are stories of this kind dating from remote epochs, and diverse decrees of parliament exist cancelling leases for this cause. These phenomena were criticised at the end of the eighteenth century.

It is only the metaphysical system founded upon these facts which is new. It is in that, and in that only, that spiritism or spiritualism consists. It is undeniable that the doctrine embodying the essence of these teachings has attained a considerable extension. I pointed out the radical differences existing between the beliefs of Anglo-Saxon spiritists and those of spiritists of other nationalities, particularly in that which concerns reincarnation. I will not go back to this; but in order to specify the point in question, I will recall to mind that the only new phenomena which spiritistic forms of contemporary mysticism offer, are their constitution into a body of religious doctrines and their rapid extension. These phenomena are of sociological, not biological order. The facts upon which they are based belong, on the contrary, to biology.

Further, it is not absolutely true to say, that the metaphysical theories established upon the revelations of spirits are new. The life of some of the ‘saints’ in the Roman Church offers us several examples, one of the most celebrated being the devotion to the SacrÈ Coeur de JÉsus,’ a special kind of worship based upon revelations claimed to have been accorded to a nun named Marie Alacoque, who lived in the eighteenth century. Monastic life has not the monopoly of such experiences. Commerce with spirits appears to be likewise one of the elements of the religious ceremonies of the Shakers; even the Mormons seem to indulge in practices similar to those of spiritism; JÉrÔme Cardan, John Dee, Martinez de Pasqually pass for having held intercourse with immaterial beings; members of the order of the Red Cross have also been looked upon as holding frequent intercourse with diverse genii. If we study the history of human thought, we see that nothing is really new, nothing save perhaps the contemporary extension of spiritism. From many points of view, spiritism appears to play a rÔle in the civilised, sceptical, material society of to-day, analogous to the simple rÔle which Christianity played in the second and third centuries of our era.

But this is a sociological problem; its examination, however interesting it may be, would lead me beyond the limits I have traced for myself. I will confine myself, therefore, to drawing from the brief historical account I have just given, the conclusion it admits of. The facts studied by Janet and others are anterior to spiritism, and cannot be legitimately designated by this name. I have already indicated that this word expresses an ensemble of metaphysical and religious doctrines explaining psychical phenomena by the intervention of spirits, and drawing their teachings from the revelations attributed to these same spirits. It is terminologically incorrect to designate these facts by a word which has a wider signification, since it expresses an explanatory hypothesis of these same facts.

Custom has consecrated the word ‘psychical’ facts or phenomena: this term is also imperfect, and it seems to me preferable to adopt the new term Metapsychical which Richet recommends.

Therefore, in the actual state of research, the scientific problem, it seems to me, is not whether spiritism be true or false, but whether metapsychical phenomena be real or imaginary.

As Richet and Ochorowicz have said, every medium may defraud, and the analysis of fraud is one of the most complicated problems which the study of psychical phenomena presents. It is also one of the most interesting. The Cambridge[37] experiments with Eusapia Paladino put clearly before us the question of fraud and its signification.

Before entering upon the psychological examination of fraud, it appears to me necessary to explain the signification of the terms I am going to use, and after that to classify medianic phenomena.

It is of primary importance to determine the correct signification of the expression consciousness.[38] There are few words in philosophical language which have such diverse acceptations. As my conception of consciousness is somewhat special without at the same time being peculiar to me, I owe it to my readers to say what I mean to designate by this term.

I conceive consciousness, lato sensu, as a function of living matter. It is the particular state which determines in organised and living matter another state of the centre where this matter lives. It is, if you like, a kind of reaction of the living matter in harmony with external phenomena. This mode of reaction, like every other mode of reaction, allows of two conditions: some sort of sensibility to the action of the ambient, permitting variations thereof to be felt; some sort of activity which permits of realising an adaptation to the ambient, and of producing internal modifications corresponding, in some measure, to the perceived external modifications. In order that the internal modifications may realise this equilibrium, they must not go beyond a certain amplitude, whence the theoretic necessity for the sensibility to be always apprised of the internal modifications of the living substance, as it perceives the external modifications of the ambient.

Experience proves that in reality things do happen in this way. In fact, we are able in the animal kingdom to prove the existence of special organs, some of them destined to the perception of the successive states of the ambient and of the individual, the others to the active realisation of the latter to the former. The different modifications provoked in the receptive system by the variations of the ambient, determine in their turn the intervention of the active system which realises the internal variations. This is the principle of the nervous and muscular systems, the latter being only put into play by the former; natural history shows us the progressive specialisation of these nervous and muscular elements. At first non-differentiated in appearance, the animal cell presents in more complicated animals a sensitive pole and an active pole, the one nervous, the other muscular. The myo-epithelial or neuro-muscular cells offer us a classical example in the hydra.

The examination of the development of the nervous system and of the muscular system in the vertebrata shows us their growing specialisation. The nervous cells are associated in systems more or less dependent the one upon the other; the muscular cells are accumulated into masses. This is the application of that law of the division of labour, the constant operation of which we observe in all the phenomena of life. The nervous cells are grouped together in a heap, in a nucleus, and send their prolongations to the periphery or to the organs. These prolongations are of two kinds: some transmit impressions towards the cell (dendrites prolongations), others transmit excitations proceeding from the cell (cylindraxes prolongations).[39] The centres themselves are hierarchised, so to speak, and are divided into two wide categories: the first destined to the functions of organic life, circulation, secretions, digestion, etc.; the second to those of the life of relation. These two categories include the sensitive cells and the motor cells; the one transmits to the other the stimulus born of excitations provoked by the internal or external centres.

In superior animals, at any rate in man, we observe that the activity of certain nervous centres is accompanied by a particular phenomenon, which is designated under the name of personal consciousness. It is the notion we have that the phenomenon is perceived by us, that the movement executed is executed by us.

Personal consciousness does not accompany all perceived phenomena, nor all executed movements. Certain given conditions of diverse orders appear necessary, for the consciousness to become aware of these phenomena. This conscious consciousness is translated by the connection of the impression or of the movement with a personality.

This personality looks to us as though it were continuous. It is around it that our past impressions are grouped in the form of souvenirs. It is that which continues the ‘self.’

The consciousness I have just described is what I call the personal consciousness. The notion of personality which characterises it is not invariable, and is not necessary.

It is not invariable, because the study of morbid psychology reveals to us that different personalities can succeed one another in the same individual, or even appear to be concomitant. This is notably the case with secondary personalities in hysteria or in epilepsy.

It is not necessary, for diverse phenomena can be perceived and stored up in the memory without the personal consciousness being conscious thereof; in the same way, movements adapted to a certain purpose may be executed without the personal consciousness being warned thereof: such are notably the reflex and complicated movements, which custom has rendered automatic.

The result of these facts is that the personal consciousness is manifested as a limitation of the general consciousness, of what I will simply call the consciousness. The study of the alterations of memory notably—diverse amnesiÆ, hypermnesiÆ, paramnesiÆ—shows us that those souvenirs of which the general and impersonal consciousness has the free disposition are incomparably more numerous than those at the disposal of the personal consciousness. This is incontestable as far as memory is concerned; is it so with intelligence? It is hard to say; there are, however, numerous examples of problems solved and of work accomplished without the knowledge of the personal consciousness.

Anatomy and physiology inform us, that personal consciousness is manifested in phenomena, which appear to have their seat in certain regions on the surface of the cerebral hemispheres. The cortical region seems to be appropriated, at least in part, by psychological phenomena, of which personality is the centre, active memory, attention, judgment, abstraction, will. It is for this reason that this region is called ‘the superior centres.’ Underneath this region the cerebral sub-cortical ganglions, the bulbous and medullary nuclei, the sympathetic ganglions, and the plexus constitute the inferior centres which preside over certain functions foreign to the personal consciousness.

However, it must not be thought that the activity of the cortical centres is always perceived by the personal consciousness. That of the motor centres, for example, may exist unknown to the personal consciousness. I have already given the indication of certain complicated movements which can be voluntary and personally conscious in the beginning, and become, in the end, unconscious and yet voluntary; e.g. the playing of a musical instrument. Likewise, certain involuntary movements can sometimes be perceived by the personal consciousness; e.g. the rapid movement we make in chasing away a fly which is worrying us. If the centre motors of the arm which drives away the fly be sub-cortical or medullary, it is none the less true that the movements executed, even when they appear to be pure reflex movements, can sometimes be perceived.

Movements executed without the participation of the personal consciousness and will are called automatic. This expression signifies for me, that the voluntary activity of the personality remains foreign to the movement executed.

Therefore, in the motor sphere, that is to say in movements, we may have different relations between the movement executed and the personal consciousness. We have, first of all, conscious and voluntary movements; then involuntary or impulsive movements, perceived or unperceived by the personal consciousness.

These diverse movements are normal: that is to say, they are executed according to the recognised rules of muscular activity; they do not go beyond the peripheral limit of the body; the nervous influx is diffused along the nerves in the ordinary manner.

If the nervous influx, or more correctly speaking, the mode of energy which constitutes it, goes beyond the material limits of the body, we have phenomena designated by de Rochas under the name of extÉriorisation de la motricitÉ. These are again automatic phenomena for me, since the personal consciousness and the will do not participate in them. But they present a feature which distinguishes them from normal automatisms: they are exosomatic, if I may use that expression, while the others are endosomatic. These two expressions signify for me, the one exosomatic, that the movements are produced beyond the limits of the body; the other endosomatic, that they are produced within the limits of the body, that is to say by muscular activity acting physiologically. The first, which are apparently contrary to the ordinary data of experience, are paranormal phenomena, that is to say, outside the usual rule; the second, on the contrary, are normal. Parakinesis is a paranormal movement with contact; telekinesis is a paranormal movement without contact.

Sensibility presents the same categories of facts. Properly speaking there is no veritable automatism in phenomena of sensitivity; but we can nevertheless distinguish therein, first, normal sensitive phenomena—that is to say, phenomena produced under physiological conditions, more or less well-known, but frequent, such as hallucinations, hypermnesiÆ; and second, paranormal phenomena, that is to say, phenomena which imply the existence of modes of perception to which the normal personality is foreign—clairvoyance, clairaudience, tele-Æsthesia, telepathy (Myers, Gurney, Podmore), exteriorisation of motor power (de Rochas).

I have already indicated that these perceptions appear to depend upon the impersonal consciousness, and that the impressions thus perceived are transmitted to the personal consciousness in a given form analogous to that of dream perceptions—that is to say, in a dramatic form, with a concrete and symbolical setting. The impersonal consciousness seems, therefore, to be affected in a vague, general manner: the perceptions only assume an appearance of precision in those strata of the consciousness, where the notion of personality is determined. Hence the following conclusions, which I only give as probabilities: (1) that the notion of personality is susceptible of diverse degrees; (2) that the impressions perceived by the general consciousness are agreeable or disagreeable—that is to say, only impart to the personal consciousness a very vague message, moral comfort or indefinable discomfort; that, in rarer cases, the transmitted message is more precise, and takes the form of a detailed hallucination; (3) that, if telepathy exists, the general consciousness is capable of being affected by channels other than those of the ordinary senses, which have only a value in ratio to the personal consciousness of which they are, perhaps, the condition.

This last consideration brings us back to the definition which I gave a little while ago of consciousness, which is, for me, the common property of all living matter: its sensuality is limited and specified by the senses, is limited and specified by the personality and the will.

I beg the reader to excuse me for having entered into these explanations. I wished, as I said before, to state as clearly as possible the meanings I attach to the terms I use; I have still another task to accomplish somewhat similar to the last: which is to classify medianic phenomena before studying their relations with fraud. In the first place I divide them into two wide categories, each capable of penetrating into the other, for, with the exception of luminosities, physical phenomena are rarely devoid of all meaning, and intellectual phenomena have always some fact of a physical nature as substratum. Therefore, these two categories are two different aspects of the same phenomena rather than two distinct categories.

If we consider the purely physical side, we have the following approximate series:—

PHYSICAL PHENOMENA

Sonorous.—Raps; diverse noises.

Motor.—Normal; paranormal; parakinesis; telekinesis.

Luminous.—Amorphous; definite forms; psychic (?) photography.

If we consider the form of communications, in appearance intelligent, by adhering to the mode of expression of the intellectual sense of the phenomena, we have the following classification:—

INTELLECTUAL PHENOMENA: ENDOSOMATIC AUTOMATISM

Muscular.—Typtology; grammatology; automatic script; automatic speaking.

Sensorial.—Visual, auditory, tactile, gustatory, olfactory phenomena.

Vaso-Motor.—Secretory phenomena; vascular phenomena; perspirations, etc.

EXOSOMATIC AUTOMATISM

(Exteriorisations): Motor.—Telekinesis; psychography (direct writing); psychophony (direct voice).

——— Sensitive-Sensorial.—Telepathy; telÆsthesia.

——— Plastic.—Materialisations; apports, etc.

On the other hand, if we examine fraud in a general manner, we will notice the following correspondences: the words conscious and unconscious are taken in the sense of the personal consciousness:—

As for true exosomatic automatism, there can be no question of fraud as far as it is concerned. This classification, which I only give as an experiment, appears to me more complete than that of Ochorowicz’s (Annales de Sciences Psychiques, vi. 97). The latter distinguishes—

If we compare Ochorowicz’s table with mine we will notice that his conscious fraud corresponds to Nos. 1 and 5 of my classification.

His unconscious fraud to No. 3.

I divide his partial, automatic fraud into the classes 2, 3, and 6.

The pure phenomenon into the classes 4 and 7.

His superior medianity includes all exosomatic automatisms (Nos. 4 and 7); his inferior medianity, the classes 3 and 6.

These general indications given, it is easy to see that I divide fraud into three categories, which are, moreover, susceptible of co-existing and of forming mixed types: this is the ordinary case. We have, first of all, the guilty, voluntary and conscious fraud; then the impulsive, but conscious, frequent fraud; then the unconscious and involuntary fraud, veritable normal automatism: the author cannot be held responsible for this last order of fraud, which is, moreover, very frequent with many excellent mediums.

If we study the psychological mechanism of fraud, we will find variable and diverse causes.

1. CONSCIOUS AND VOLUNTARY FRAUD

The most usual cause is self-interest. This is the case with charlatans, who speculate upon the credulity of the public. We must not think this is the only motive; each impostor obeys motives which are peculiar to himself. The medical student, who gave me such curious examples of fraud, was not actuated by motives of self-interest. I think it was simply for the pleasure of cheating, of taking me in, for I had often spoken to him about my suspicions. He often cheated simply as a prank; this is what happened in a seance given by a spiritistic group to convince some new converts, when my student, it appears, gave them manifestations somewhat out of the common!

However, conscious and voluntary fraud raise no real psychological problem.

2. CONSCIOUS AND INVOLUNTARY OR MIXED FRAUD

On the contrary, the problem originates in this order of fraud. It often happens in circles, though composed of honourable persons, that some of the sitters, who would be incapable of voluntarily committing a fraud, do not dare to accuse themselves of an involuntary movement made by them, and of which they are conscious. This can only be applied to fairly rapid movements, such as those which imitate raps or parakinetic movements. In serious seances, the sitters should give themselves the habit of openly acknowledging every involuntary movement; it will be noticed that certain persons are very prone to these movements. They often end by being ashamed of accusing themselves so often, and thus fraud from timidity: I have met with this, especially among women. It is one of the reasons which make me condemn all experiments for the production of movements with contact.

Timidity is the usual cause of this kind of fraud: the psychological problem raised is simple.

3. UNCONSCIOUS AND INVOLUNTARY FRAUD

Here the problem becomes complicated. I will not distinguish, as Ochorowicz does, fraud committed in the waking state from fraud committed in the trance or second state. The psychological mechanism is the same in both cases, and appears to me to depend upon self-suggestion, or what has been called monoÏdeism, that is to say, the mind is invaded by one idea, which ends by stifling all others, and by realising itself: it is, in reality, a phenomenon analogous to that determined by suggestion.

It is in unconscious or involuntary frauds, that the psychological disaggregation of the medium which Janet has studied, is best observed. These frauds present phenomena which are without interest from a medianic point of view.

What is the mechanism of unconscious and involuntary frauds? It appears to me to be the following: the subjects—they may have been good mediums in their day—who commit this kind of fraud sit down to the table, or give a seance in view of obtaining supernormal phenomena. But the production of these phenomena is often difficult, sometimes impossible. Immobility, expectation, and obscurity act powerfully upon the nervous system of these mediums, and particularly so when they are hysterical. They determine the trance; the desire for the phenomenon becomes a fixed idea, and then a self-suggestion. If the supernormal phenomenon delays, the inferior strata of the consciousness—whose morality often differs greatly from that of the active personal consciousness—realises it normally.

In the same way, even if the sensitive does not fall into the trance state, there is, nevertheless, a particular state manifested which is not sleep, neither is it the full, genuine waking-state. The active and voluntary personal element of the consciousness, as well as the judgment, becomes weakened. The sphere of the personality is reduced, and personal activity gives place to automatism. Every degree between conscious and involuntary fraud and pure automatism is to be met with.

Therefore, it is prudent to take measures to guard against fraud with all subjects who become entranced, or with those who become somnolent in obscurity, silence, immobility, and expectation; but we should be frank with our sensitives: let us not offer, in ourselves, an example of dissimulation to the medium; neither must we let him have the impression of not being controlled: this would be to expose him to a temptation, all the greater in that his personal power of volition is weakened.

Add to this, that we do not in the least know what influence the mental state of the experimenters has upon the medium, although some kind of influence appears to me to exist. We do not know to what extent an ill-founded certitude of fraud can be responsible for its birth. Ochorowicz says on this subject:—

‘After having recognised that the medium is only a mirror, who reflects and directs the ideas and nervous forces of the assistants towards an ideoplastic end, we will not be surprised to see that suggestion plays an important rÔle therein. There is no doubt but that the assistants can suggest the desired act to the medium; neither is it doubtful that the manifestations bear the stamp of surrounding beliefs. In a society of materialists I have seen “John” (with Eusapia Paladino) become dissolved into an impersonal force, which the medium simply called “questa forza,” while in intimate spiritistic circles it took the form of deceased persons, more or less clumsily. In the same way, with controllers imbued with the idea of fraud as Messrs. Hodgson and Maskelyne were, the medium will remain under the empire of a suggestion of fraud.’

Without completely sharing Ochorowicz’s conviction, I have reasons for thinking that his theory comes very close to the truth. I have myself indicated how suggestible the personification is.

There is something else. In cases where force is lacking, or is feeble, it is easier for the medium to obtain the phenomenon normally—that is to say, by fraud—rather than by veritable exteriorisation. I have remarked, that often the paranormal movement has to be normally simulated before it is supernormally realised. This is frequently the case with Eusapia. We can conceive how the movement of simulation can end in fraud, when the medium is in a hemisomnambulistic state.

In short, the energy which sets an object in movement appears to me to be of nervous origin, and I believe it to be of the same nature as that which provokes muscular contractions. Therefore, this is what follows: the force only becomes exteriorised if accumulated and wrought up to a sufficient tension. In proportion as its tension increases, so it tends to expend itself in the form of impulsive movements; the medium must resist this tendency to be able to obtain the pure phenomenon. Therefore experimenters ought to keep the medium in this resistance, and not allow him facility for expending the energy which tends to realise itself in muscular movements.

Such are the conclusions to which the observations I have made with several mediums have led me. Unconscious and involuntary fraud is frequent, and in order to avoid it, the conditions likely to favour it should be carefully put aside, especially in the beginning of a series of experiments, and when experimenting with an undeveloped medium. Medianity is powerfully influenced by acquired habits.

There exists, finally, another kind of unconscious and involuntary fraud: that which is due to illusion. It is constantly found in spiritistic seances, where ninety-nine times out of a hundred mediums produce no real phenomena. They are, nevertheless, in earnest, but they do not take into consideration the rÔle of memory and imagination. This is particularly the case with intuitive writing mediums and ‘control’ mediums. With this order of phenomenon we rarely obtain verifiable indications; the ‘spirits’ utter plenty of commonplace generalities, but give no precise information.

Fraud is a misnomer in this case: being unconscious and involuntary, it cannot, correctly speaking, be called fraud; therefore it is better to reserve the word ‘illusion’ for it.

I cannot think of analysing the question of fraud in detail. If examined closely it is extremely complicated. But, like Richet, I deem ‘it possible that in states bordering on trance, and in trance itself, the psychology of a medium may be very different from ours.’ I confine myself simply to indicating the result of my reflections, which are the fruit of a long series of observations. Let me renew my oft-repeated recommendation for avoiding fraud: Experiment with light, the greatest possible amount of light, and seek for simple phenomena, difficult, perhaps, to obtain, but easy to observe, such as raps and movements without contact.

II. ERROR

If I insist so much upon the necessity, especially in the beginning, of seeking only for phenomena observation of which is easy, it is because error of observation is facile. We need to be much accustomed to seances to be able to distinguish rapidly between probable phenomena and those which are certainly tricked. It is with this, as with everything else, a question of time and reflection.

One of the causes of error, which it is highly important to avoid, is obscurity. For many simple phenomena darkness is unnecessary; therefore, from the very outset, we should exhort the personification to accept light. I have already frequently said that personifications are very suggestible. I know well it is not always so, and that at times the personification displays much obstinacy. Personifications of this class are especially observed with mediums who have long-acquired habits. It was so with Eusapia, who was only accustomed to giving dark seances. But even when the personification appears to have very decided ideas, it is possible, with a little ingenuity, to induce him to change. It is with them as with secondary personalities, or subjects to whom we have given a suggestion. We must enter right into the circle of suggested ideas in order to break it; it is a question of tact only.

With Eusapia we succeeded in operating in a good light by appealing to ‘John’s’ vanity. We explained to him that obscurity stood in the way of the observation of the phenomena, that he was just as capable of working in the light as the ‘guides’ of other mediums were. In this way, we lead him to change his habits with us; the meno luce to which those who have experimented with this medium are accustomed, was still demanded, but only when the seance was well advanced. At Bordeaux, where there was a large bay-window in the seance-room, the reflection thereon from the lights burning in the kitchen and winter-garden enabled us to see a little. In that case, Eusapia or John did not desire total obscurity, and we always had this feeble light, allowing a visual control which was sometimes satisfactory.

When we are lucky enough to meet with an undeveloped medium, it is easy to give him the habit of operating in full light. This has occasionally happened to me.

I need not enlarge upon the influence of obscurity upon error. With some very rare exceptions we can never be certain of the authenticity of a phenomenon obtained in a dark seance.

Obscurity is, however, necessary for luminous phenomena. When once we have observed decided luminous forms, or really characteristic lights, it is easy to distinguish between them and illusion. A cool, calm observer does not make a mistake; it is not quite the same with excited experimenters. These latter give veritable suggestions to one another, and they end by having curious collective hallucinations. This is one of the most interesting facts of observation in spiritistic seances, so rich in purely psychological curiosities. I have frequently heard a sitter say that he saw a light in a given direction; the others looked in their turn and also saw it. Then one declared he perceived a form; soon others also saw a form. And from exclamation to exclamation the description of the form is completed. This is the genesis of a collective hallucination.

I need hardly say, that experimenters who are so suggestible are not good elements: in purely scientific researches they should be reduced to a minimum.

Personal experience has shown me, that of all the senses, that of sight is the most liable to imaginary impressions; after sight, the sense of touch is the most prompt to receive illusion. There are constant examples of this in spiritistic seances; the cool breeze, which is often really felt, is more often only imaginary. One person says he feels it; others at once imagine they feel it also. Sometimes it is not an error of imagination, but an error of attribution, the sensation of a cool breeze being caused by the breath.

The sense of hearing has seemed to me to be refractory to suggestion in seances, though it does not altogether escape. I know of very few examples of imagined raps or noises.

On the contrary, the muscular sense is one of the most unfaithful. Unless one has experimented oneself, it is impossible to imagine how frequent unconscious and involuntary movements are. These movements are of very feeble amplitude; they are slight, but they end by acquiring a certain amount of force. It will then be noticed that the assistants accuse each other reciprocally of pushing the table, and it is not rare to see angry discussions arise on these occasions. This is a frequent fact of observation. I have also very frequently noticed tactile hallucinations with impressionable experimenters, who easily imagine diverse contacts.

The sense of smell sometimes perceives imaginary odours, but it is somewhat rare. I have not observed any hallucinations of taste.

Another cause of error which requires pointing out is fatigue on the part of the experimenters. Every phenomenon which is produced after a long period of waiting stands many chances of being badly observed. The attention kept for a long time on the qui vive becomes weary, gives place to abstraction, and often the phenomena takes the experimenters by surprise; hence they are unable to examine the conditions with certitude. It is also bad to hold very long seances, fatigue quickly setting in.

Such are the principal causes of positive errors; that is to say, of errors tending to persuade one of the existence of an imaginary fact; negative errors, that is to say, those which tend to make one look upon a real fact as an imaginary one, are not less dangerous than positive errors.

In the first place, parti pris is to be pointed out. If we wish to experiment with success, we must experiment without credulity, without faith, even without confidence; but we must not be determined only to meet with fraud.

We must not experiment naÏvely. If, at the beginning of a seance, it be useful to allow freedom in order to put the force en train, as Ochorowicz wisely recommends, once the phenomena are established, we must control them with the greatest care. But we should make our intentions known to the medium and to the personification. This, I think, is an indispensable precaution. The personification will always consent to it; but this does not mean we will always obtain the wished-for result. We must not allow the medium or the personification to think we are their dupes if they fraud; we must tell them, gently but clearly, that they are not giving anything good. Equivocation is to be carefully avoided, all misunderstanding is to be shunned.

We must not, however, place the medium under such conditions that the experiment cannot be realised. We do not understand these conditions, and, perhaps, apparently simple phenomena may not be realisable. I remember that at Choisy in 1896, a lady, a member of my family—she has an insurmountable bias against psychical experiments, which she declares a priori are fraudulent—declared to Eusapia that she would believe in her phenomena, if she could make a doll’s table move before her eyes. Eusapia placed this small table on top of the seance-table, but did not succeed in making it move. Why could not such an apparently simple phenomenon be obtained?

We must, therefore, observe, but we must not wish to impose beforehand the conditions which the phenomenon should fulfil in order to be accepted.

Many experimenters tie up the medium, put him into a sack, and seal him therein. If he consents to this, well and good; if he refuses, other means of control must be found. We must not indeed suppose that the medium’s refusal is always due to a desire to fraud. The slightest fetters may sometimes be very painful, especially when there be cutaneous hyperÆsthesia.

Before bringing a negative judgment to bear upon the phenomena, the experimenters should always hold a certain number of seances, and should not found their judgment upon one bad seance alone; by so doing they would expose themselves to a wrong course of action.

It is especially in psychical experimentation that inexhaustible patience is necessary.

[37] See Appendix B.