NOW WE come to the subject of the first part of this book, the description of the manifold possibilities of deception against which the serious psychical researcher has to take precautions. I shall have to be very strict here, for even the tiniest loophole left unstopped can admit some form of deception.
First of all I shall discuss the possibilities of deception in the course of the actual investigation of the facts, and secondly the possibilities of theoretical error. The former of these is by far the more important.
English investigators have sometimes said that the psychical researcher must possess in equal degree the qualities of the natural scientist, the psychologist, the psychiatrist, the magistrate, and the conjurer. This is true, and the remark shows how difficult is our task; I need hardly add that in everything that follows, when I describe a series of necessary precautions, I set these out as an essential minimum, without in any sense claiming completeness. I should be very grateful for any additions to my catalogue of deceptions.
There are two ways in which knowledge is acquired in any investigation of phenomena: observation and experiment, which is observation, in essentials, under specific conditions voluntarily and deliberately determined.
Now, in describing the possible means of guarding against deception, we must distinguish, as in all scientific work, between observation and experiment. For the rest, a profitable investigation into our field of inquiry can only be made after some general considerations have been brought forward regarding this distinction between experiment and observation as it applies specifically to psychical research. For matters are somewhat different here than they are in the normal natural sciences.
When the natural scientist carries out a normal experiment, whether in the realm of the inanimate or in that of the animate, he enters on his investigation with the definite expectation that 'something' will happen, and he does so for the purpose of ascertaining the nature of that 'something.' Strangely enough, this 'something' can be a specific kind of 'nothing,' which nevertheless remains 'something' just because it is a
specific 'nothing.' For instance, in experiments in regeneration, if the amputated limb of an organism does not regenerate, then it either grows a new skin over the wound or dies. And that is 'something,' although it is not what was anticipated. It is significant that the organism, if it is a mammal, does 'not' regenerate. And what is most important is the fact that what I may call the not-result is tested again and again under identical conditions and is always 'obtained': it thus becomes a law.
In psychical research, however, sometimes something happens and sometimes nothing at all, even though the conditions are identical on such occasions so far as they are within the control of the experimenter. In short, the certitude and uniformity of expectation are absent in experiments in psychical research. It will be said that this is not so very different from conditions in normal scientific investigations. In biology, and even in inorganic work, though less often, it can happen that in a long series of experiments a 'specific nothing' may regularly occur, only to be interrupted by the occurrence of 'something,' notwithstanding the fact that the conditions are identical so far as they are within the control of the experimenter. It may also happen in a long series of experiments that a certain 'something' is replaced by quite another 'something'(1). This criticism is certainly justified. It is said in such cases that there existed highly variable 'inner' conditions of the organism which were not within the control of the experimenter, but of which he now obtains control. Might not even a mammal 'suddenly' produce phenomena of regeneration? We should be surprised if this happened - and then investigate further. Was not the saying that stone walls never transmit electromagnetic radiation proved false by X-rays?
(1) An example of this can be seen in my investigations into the restitution of Tubularia and Ascidia
("Archiv fur Entwicklungsmechanik", vols. v. and xiv.).
It is nevertheless true that in psychical research, as for instance in experiments in thought-transference, this state of affairs occurs much more readily than it does in normal scientific work. Negative experiments in psychical research, by which I mean in this context experiments in which a specifically awaited event fails to occur, must be studied with great caution before they are regarded as radically negative: a fact which will later play an important part in our critical discussion. The reason for this great caution is the fact that in psychical research the investigator has less control over the 'inner conditions' than he has in biology and still less than he has in organic science.
Spontaneous and Anticipatory Observation
When observational psychical research is further examined it is found necessary to divide it into spontaneous and anticipatory observation, the latter of these two types being already a very primitive kind of experiment.
All true telepathy, at the time of danger to life, and all true haunting, if we admit this phenomenon, can only be observed spontaneously, at any rate in their primary stages. That is, according to the testimony of certain persons stated phenomena simply occurred and were set down. The same is true of apports, if we are to accept these as genuine phenomena.
As soon, however, as we are confronted with an alleged haunted house or with a person in whose presence apports are said to have taken place or who is said to have been the source of telepathic communications, then things are otherwise: anticipatory observation begins and we are already carrying out an elementary sort of experiment, in the hope that something 'may' happen.
It is clear therefore, that it is particularly in this field that we have to apply the precautionary measures to be described. Verification
post factum, that is, corroborative inquiry after the event, which is all that is possible in spontaneous phenomena, does not in the least deserve to be described as real verification. In such cases it is only possible to establish whether the phenomenon
may have been 'genuine.' This can be done sometimes with less, sometimes with greater, certitude - in spontaneous telepathy, as we shall see, often with very great certitude.
It should hardly be necessary to say that true experiment is the most adequate way of investigating the laws of empirical reality. Experiment allows the strictest precautions against deception to be taken, and it is by its very nature capable of being repeated at will, so that in theory an infinite number of cases are available for investigation. Thus anticipatory observation is the more valuable the nearer it approaches to experiment; I shall have much to say in the following pages about this type of investigation.
Spontaneous observation can only seldom claim decisive scientific significance, and then only on certain definite grounds, which will be explained later. If it leads to experiment or even to anticipatory observation, then of course the case is altered; but then it is no longer 'spontaneous' observation.
It is to-day customary in some quarters to put aside all experimental work and even all carefully conducted anticipatory observation as 'exaggeratedly critical,' and to seek salvation in the procuring of numerous cases of spontaneous observation. I have nothing at all against the study of such cases, if only they do not rest quite exclusively on pure hearsay. Discussion of them may arouse a desire for critical investigation. But in and by themselves (apart, as we shall see, from spontaneous telepathy) such cases have very little significance; until they have been investigated they remain mere assertions. And is it even possible to be 'exaggeratedly critical'? Other sciences do not think so!
I will now, reserving precise definitions for a later section, briefly and provisionally classify the phenomena of psychical research into the three categories to which they belong; spontaneous observation, anticipatory observation, and experiment. In doing so I as yet pass no judgment on the reality of these alleged phenomena. I think I may assume that the reader will have a general notion of the phenomena represented by the terms that follow.
In the field of spontaneous observation we find the following phenomena: all cases of true telepathy; many cases of thought-reading, clairvoyance and prophecy; hauntings, materialisations, apports, telekineses, phantasms, in their primary stages, that is, on their first and unexpected occurrences.
Anticipatory observation is undertaken in so-called sittings for certain physical phenomena, as well as in hauntings, or in the investigation of these phenomena by 'commissions'; many cases of thought-transference, clairvoyance and prophecy, very often in the form of psychometry; telekineses, materialisations, apports, hauntings, in their secondary stages, that is, after they have already been spontaneously observed in relation to specific people or specific places, so as to give rise to the supposition that something will very likely happen.
So far only conscious (not spontaneous) telepathy and thought-transference have been made the object of experiment in the strict sense of the word, and even these not very often; and quite recently telekineses, by