Atheism Central for Secondary Schools
|Site links||Parapsychology and the paranormal - by Dr Christopher C French|
Paper presented at the British Association Annual Festival of Science
10 September 1996, University of Birmingham
Dr Christopher French, BA PhD CPsychol FBPsS
Department of Psychology,
Goldsmiths' College, University of London
The Journal of Parapsychology (1994) defines psi as "A general term used either as a noun or adjective to identify ESP or PK." ESP or extrasensory perception is then defined as "Paranormal cognition; the acquisition of information about an external event, object, or influence (mental or physical; past, present, or future) in some way other than through any of the known sensory channels." This term subsumes telepathy (direct mind to mind contact), clairvoyance (acquisition of information relating to remote objects or events), and precognition (knowledge of future events other than by ordinary deduction). PK or psychokinesis is defined as "Paranormal action; the influence of mind on a physical system that cannot be entirely accounted for by the mediation of any known physical energy." PK is often subdivided into micro-PK, defined as "Any psychokinetic effect that requires statistical analysis for its demonstration. Sometimes used to refer to PK that has as its target a quantum mechanical system," and macro-PK, defined as "Any psychokinetic effect that does not require statistical analysis for its demonstration; sometimes used to refer to PK that has as its target a system larger than quantum mechanical processes, including microorganisms, dice, as well as larger objects."
Giving a strict definition to the term paranormal is problematic, but in a general sense the term is used to refer to alleged phenomena which cannot be accounted for in terms of current scientific theories. Some researchers adopt a strict interpretation of the paranormal as only including ESP and PK, but the term is often used much more widely to include a range of phenomena such as astrology, UFOs, dowsing, the Bermuda triangle, firewalking, and so on.
The scientific status of psi is still hotly debated (see, e.g., Rao & Palmer, 1987; Alcock, 1987). Critics point out that parapsychology has been plagued in the past by methodological problems and occasional fraud by subjects or experimenters. Recent evidence, to be discussed more fully by Deborah Delanoy later today, presents the strongest challenge to date to those sceptical regarding the reality of psi, but the history of parapsychology has involved many false dawns and a "wait-and-see" approach to the latest evidence is not entirely unreasonable. There is no doubt that if psi is real, many aspects of our current scientific world-view will need to be radically overhauled and such a task is not to be undertaken lightly.
Turning to the views of the general public, opinion polls typically reveal a high level of belief in paranormal phenomena. For example, in one recent survey a representative cross-section of the British public were asked for their opinions relating to various paranormal claims. The percentage indicating that they thought that a particular claim was true is given after each statement:
Fully 88% of the sample agreed with at least one of the above statements. In the eyes of the general public then, the paranormal is real.
Such high levels of belief represent a challenge to those who doubt the reality of the paranormal. It is not simply in modern Western society that we find high levels of belief. Throughout history and in all societies we find allegedly true accounts of events which, if they really did occur, fit our definition of the paranormal. Religious texts such as the Bible contain many accounts of miracles, including healing, precognitive dreams, and psychokinetic wonders such as walking on water and turning water into wine (not at the same time, I should point out). In ancient Greece and Rome, many forms of divination were accepted as true guides to what the future held, including the interpretation of animal entrails, which was much messier than reading tea leaves and probably no more accurate. In many traditional cultures even today, it is accepted that certain gifted individuals have special powers that enable them to communicate telepathically, pick up information clairvoyantly, or place a deadly curse upon their enemies.
Can the critics of the paranormal really be justified in rejecting this almost universal belief in psi? The short answer is that at the moment we simply do not know whether or not paranormal forces exist and a truly scientific and open-minded approach must be one that allows for the possibility that they might. What we can be sure about, however, is that even if such forces do not exist, human nature is such that many people would still believe in the paranormal. This is at least partly because of the imperfections in the way that we process information about the world around us. In many situations in everyday life, events can occur which many people feel can only be explained in terms of the operation of paranormal forces but which can in fact be accounted for by the operation of known physical or psychological factors (Alcock, 1981; Blackmore, 1990; French, 1992a; Hines, 1988; Hoggart & Hutchinson, 1995; Zusne & Jones, 1989). Whether or not this approach will ultimately explain away all paranormal claims remains to be seen, but it is probably true to say that most serious researchers on both sides of the debate would agree that most events which are interpreted in paranormal terms do not involve psi.
A few years ago I reviewed this topic and listed numerous situations which people often interpret in paranormal terms but which in fact require no such explanation (French, 1992a). I also considered the question of whether or not some people might be more prone than others to the kind of biases in processing information which might lead to such misinterpretation. This might account for the fact that people differ in terms of their level of paranormal belief. At one extreme is the dogmatic sceptic who refuses to accept even the possibility that paranormal forces may exist without actually considering the evidence at all. At the other extreme is the type of person who will accept any paranormal notion on the basis of the flimsiest of evidence. Most people are somewhere in between. Today, I do not intend to present a comprehensive review of this approach but instead to give illustrations of some of the factors which my colleagues and I have considered in recent investigations. It is worth pointing out that no single psychological factor will provide a full account of paranormal beliefs and experiences, given the wide range of paranormal beliefs and experiences that exist. However, each of the factors which have been investigated might provide another piece in the jigsaw.
People are notoriously poor at estimating probabilities (Kahneman, Slovic & Tversky, 1982). For example, if asked "How many people would you need to have at a party to have a 50:50 chance that two of them share the same birthday (ignoring year)?", most people are surprised to learn that the correct answer is 23. It follows that if people do not appreciate how likely a particular event is on a chance basis alone (e.g. a precognitive dream 'coming true'), they may be reluctant to accept an explanation which says that it was just a coincidence and prefer instead a paranormal explanation. Caroline Watt will consider the psychology of coincidences in some depth later today, but I would like to give you just one powerful illustration of the relevance of coincidence in explaining ostensibly paranormal events.
Mathematician John Allen Paulos (1990) illustrates the fact that we would expect numerous reports of apparently "precognitive" dreams every year purely on the basis of chance. For the sake of argument, let us suppose that we define a dream as "apparently precognitive" if the chances of the dream matching some future event in one's life are as low as one chance in 10,000. Surely, all of us would be impressed if we were the person who had such a dream. Again, we will simplify matters by assuming that each person has one dream per night (in fact, we all have a lot more). The probability that any one dream will not be apparently precognitive is high (.9999). The probability that over a whole year, one will not have a dream which appears to predict the future is given by
In other words, even over a whole year the chances are that you will not have such a dream. But around 3.6% of the population will have at least one such dream! This amounts to 9 million people in the USA alone. Furthermore, any single person, over a 19-year period, will have a slightly better than even chance of one such dream. Even if you think that 1 in 10,000 is too high, and opted say for odds of 1 in 100,000 before classing a dream as "precognitive", you would still have 900,000 reports per year in the USA without any need to invoke psychic powers whatsoever. In fact, of course, it is likely that other non-paranormal factors are often involved in people having ostensibly precognitive dreams, e.g., dreaming of an elderly relative dying when one already knows that they are ill.
Another factor which can lead to people resorting to a paranormal explanation unnecessarily is when an alleged psychic fools them by using conjuring techniques. Singer and Benassi (1981) report a series of studies in which an amateur conjuror performed various tricks in front of introductory psychology classes. Regardless of whether the performer was introduced in a sceptical tone as an alleged psychic or as an amateur magician, three-quarters of the subjects believed strongly that the performer was psychic. In further studies, a majority of subjects thought that the performer was psychic following a neutral introduction. When asked if magicians could perform similar stunts, nearly all subjects agreed. They also agreed that the majority of people who did such tricks were likely to be magicians or fakes, not genuine psychics. However, when subjects were asked to reassess the performance in the light of their own subsequent statements, they again claimed that the magician was psychic.
One is reminded of an incident involving James ("The Amazing") Randi as witnessed by psychologist James E. Alcock:
Richard Wiseman and Robert Morris (1995) have recently presented evidence suggesting that believers may have poorer memories for what actually occurs during a "pseudo-psychic" demonstration (i.e., conjuring) and be more prone to rate the demonstration as involving paranormal forces.
One particular technique which is popular with pseudo-psychics is known as "cold reading." Cold reading can be used to give the impression that one is able to know all about complete strangers (Dutton, 1988; Hyman, 1977; Roe, 1995). Obviously, this technique can be exploited to convince people that one has psychic powers. There are many cues that can be used to predict a lot about people before they even open their mouths - age, sex, clothing, jewellery, hairstyle, and so on. The cold reader, be they psychic, astrologer, palmist, or whatever, has a keen eye for such details. Once the consultation begins, however, the cold reader is apparently able to quickly "zoom in" onto the area of concern and tell the client all kind of things that they apparently could not possibly know without psychic powers. In fact, the cold reader makes use of subtle cues from the client, such as changes in posture, tone of voice, and breathing rate, to skilfully home in on areas of greatest interest to the client. By a subtle mix of intelligent guesswork and feeding back information which was actually supplied by the client in the first place, a powerful illusion can often be created that the reader is indeed in touch with some psychic source of knowledge.
It is a moot point to what extent self-proclaimed psychics deliberately exploit the techniques of cold reading as opposed to using them unconsciously and actually believing that they really do possess a special psychic gift. What is absolutely certain, however, is that the technique can be used very effectively by those who make no claims whatsoever to such gifts.
One aspect of cold reading which has received a great deal of attention from psychologists is a phenomenon known as the Barnum effect. This refers to the tendency for people to accept vague, ambiguous and general statements as descriptive of their unique personalities (for reviews, see Dickson & Kelly, 1985; Furnham & Schofield, 1987; Snyder, Shenkel, & Lowery, 1977). This typical Barnum profile illustrates the power of this technique (imagine you were being given this description of yourself by a psychic or an astrologer):
Many ostensibly paranormal experiences involve trying to find matches between two rich and complex sources of information. An example would be clients listening to psychic or astrological readings and attempting to make sense of them in terms of the events in their own lives. The sources of information in this case are, on the one hand, the reading itself, which is typically vague, rambling and verbose, and, on the other hand, the rich tapestry of a human life. It is not surprising that matches can be found if the client is inclined to look for them. Marks and Kammann (1980) coined the term 'subjective validation' to refer to this tendency to find matches between unrelated stimuli: "This occurs when two unrelated events are perceived to be related because a belief, expectancy, or hypothesis demands or requires a relationship" (p. 24).
Marks and Kammann (1980) originally coined this term to refer to an interesting effect which they had noticed when carrying out remote viewing studies. Other researchers (e.g., Targ & Puthoff, 1974) had reported that the remote viewing technique produced reliable evidence of paranormal transmission of information. A typical remote viewing study might involve one person, the agent or "sender", visiting a number of randomly selected sites (e.g., a park, a bridge, a railway station, etc.) and attempting to telepathically transmit information to another person, the "receiver", back at the laboratory. At prearranged times, when the sender was at the target locations, the receiver would describe any mental images and impressions that they were picking up and the experimenter would record and transcribe everything said. These transcripts would then be given to independent judges who would visit the sites and rate the degree of match between each transcript and each site.
Marks and Kammann (1980) did not find any evidence for ESP and presented compelling evidence that the success of previous studies was probably due to flaws in the methodology employed. What they did notice, however, was that the independent judges, when visiting the sites after the experiment, would sometimes get terribly excited over some correspondence between details in the transcripts and at the scene being visited. It turned out, however, that the transcript would usually not be the one which had been produced when the agent was visiting that location. In other words, the match was coincidental, purely the result of trying to find correspondences between two very complex stimuli, the transcript and the location. This situation was well described by Scott (1988, p. 322):
It should be noted at this point that a properly conducted remote viewing study would actually be immune to biasses arising as a result of this human tendency to find correspondences between two complex and supposedly related stimuli. In fact, remote viewing studies continued to be carried out following Marks and Kammann's (1980) critique and currently constitute one of the approaches which parapsychologists feel provide strong evidence for the reality of psi (see. e.g., Utts, 1995a, 1995b; Hyman, 1995). Whether or not they are right, my colleagues and I were interested in the possibility of using the remote viewing technique as a cover story to investigate possible differences between believers and non-believers in the paranormal.
In three experiments, carried out in collaboration with Dominique Herrmann, Sandra Hales and Charlotte Northam, believers and disbelievers in the paranormal were asked to evaluate evidence ostensibly obtained from remote viewing experiments. Subjects believed that they were judging the degree of match between sets of photographs of sites visited by a telepathic sender and transcripts of descriptions of those sites produced by a telepathic receiver. In fact, all transcripts were produced by the experimenters and thus the degree of match was under experimental control. Believers rated the degree of match and the probability that ESP was operating higher than disbelievers, even when any match between photographs and transcripts was entirely coincidental, because the transcripts were paired with completely unrelated sets of photographs. In the final experiment, this effect was found to apply only when believers were under the impression that the transcript was paired with the actual target, not when they were told that the transcript was a control transcript included for comparison purposes. We carried out the final experiment in order to investigate the possibility that believers might simply perceive more matches than disbelievers between two stimuli regardless of whether or not they had been led to believe that the stimuli were psychically linked in some way. Previous work by Richard Wiseman and Matt Smith (1994) had supported just this possibility and the reasons for the apparent discrepancy between our findings and theirs are currently unclear.
Another situation which is commonly misinterpreted as involving paranormal powers, but in fact does not, is the demonstration of population stereotypes. If a group of subjects are told that a number, say, between one and ten is to be telepathically transmitted to them and that they are to write down the first number that comes into their minds, their responses will be far from randomly distributed. In fact, "7" will be by far the most popular response regardless of the number that the 'sender' had in mind. Similar effects are found using other types of target (e.g., for "a simple line drawing," a sizeable minority of subjects will draw a house). These effects have been exploited by Uri Geller, amongst others, to give the impression that psychic forces are at work when in fact they are not.
Whilst the basic effect itself is very reliable, it is unclear whether believers in the paranormal are more prone than disbelievers to respond in line with stereotypical responses in such situations. Research on that issue to date has produced a mixed pattern of results (e.g., Marks & Kammann, 1980; Grimmer & White, 1986; Rigby, 1989; French, 1992b). Such an effect is intuitive plausible. If some people tend to think in more stereotypical ways, they would more often find other people saying just what they were thinking and might therefore be more inclined to believe in telepathy. On the basis of the mixed results from previous research and a successful pilot study involving 135 subjects, in which believers did indeed demonstrate stereotypical responding to a greater extent than disbelievers, Susan Blackmore and I recently were able collect data from a very large sample thanks to the BBC's Tomorrow's World programme. We had an actor play the role of a psychic. Viewers were told that he was trying to transmit a number, which was less than 50 and has two digits, with both digits odd and not the same. They were told, "So he might be thinking of 15 - one and five are both odd - but not 11 - one is odd, but both digits are the same." Typically, about one third of an audience will produce "37" in response to these instructions, which is the result we obtained from almost fifty thousand callers. In case anyone is wondering whether our actor might really have been psychic and caused this dramatic peak in response distribution, we had told him to concentrate on "19" which, predictably, was chosen by few of the respondents. We also obtained a highly significant difference between believers and nonbelievers in terms of the degree to which they tended to produce the stereotypical response. Unfortunately, it was in the opposite direction to that predicted! Any suggested explanations would be gratefully received. Clearly, further research is required.
Both of the examples discussed relate to what we might call information processing (or cognitive) biases, but there is no doubt that other psychological factors are also important in accounting for paranormal beliefs. A vast amount of research has been directed towards looking for personality differences between believers and disbelievers and interesting results have been found (see Irwin, 1993), although once again a thorough review is impossible in the time available. Michael Thalbourne and Peter Delin (1994) recently put forward an interesting hypothesis in an attempt to account for a pattern of correlations which is repeatedly found in the literature. Belief in the paranormal is significantly correlated with creativity, the tendency to experience mystical states, and various measures of psychopathology. Thalbourne and Delin have argued that a single factor, which they refer to as "transliminality," might underlie these associations. In their words (p. 3):
It should be noted that Thalbourne and Delin's hypothesis is essentially neutral with respect to the issue of whether or not ostensibly paranormal experiences truly involve paranormal forces. It may be that individuals with a high degree of transliminality simply cannot distinguish between reality and the products of their own minds and their reports of paranormal events may not reflect objective reality at all. On the other hand, it may be the case that psi really does exist and that this type of individual is particularly likely to experience it.
Several recent papers have considered the importance of childhood factors in the development of paranormal beliefs with a particular emphasis upon the personality characteristic of fantasy proneness (e.g., Irwin, 1992, 1993; Lawrence, Edwards, Barraclough, Church, & Hetherington, 1995). Fantasy prone individuals spend a lot of their time engaged in fantasy, have particularly vivid imaginations, and make excellent hypnotic subjects (Lynn & Rhue, 1988; Wilson & Barber, 1983). Fantasy proneness has been shown to correlate with level of paranormal belief and personal experience of ostensibly paranormal events (e.g., Irwin, 1990, 1991; Lawrence et al., 1995; Myers & Austrin, 1985; Rao, 1992; Wilson & Barber, 1983).
Wilson and Barber (1983) noted a high incidence of childhood trauma, ranging from physical abuse to unstable living conditions, in their fantasy prone subjects. One third of the fantasizers reported childhood trauma compared to none of the matched controls. Although it is recognized that fantasy proneness may develop simply as a consequence of encouragement to fantasize from an important adult in the child's life, childhood trauma is widely considered to be a major developmental antecedent. It is possible that such fantasy offers escape from an aversive situation (Lynn & Rhue, 1988; Rhue & Lynn, 1987).
This idea was supported by Harvey Irwin (1992) who reported a marginally significant correlation between scores on a measure of paranormal belief (Tobacyk, 1988) and a measure of childhood abuse (Council & Edwards, 1987). Irwin (1993) proposed a model of the origins and functions of paranormal belief in which fantasy proneness played a central part. In his model, fantasy proneness could develop either as a result of encouragement of fantasy in childhood or as a consequence of traumatic childhood experiences. In the latter case, fantasy proneness was mediated by the need for a sense of control. A subsequent study by Lawrence et al. (1995) supported the statistical association of childhood trauma, childhood fantasy, and paranormal belief and experience, although these authors suggested some slight modification to Irwin's original model.
The studies by Irwin and Lawrence and colleagues relied upon retrospective reports of childhood abuse from adults, usually obtained by questionnaire. There are at least two ways in which that method could produce invalid findings. It may be that those subjects classed as fantasy prone are simply more honest. They may be willing to admit to having a rich fantasy life even though such an admission may leave them open to the accusation of being "a little odd" in our society. Similarly, to profess one's belief in various paranormal phenomena and to admit to having had paranormal experiences may leave an individual at risk of ridicule from others. Finally, it goes without saying that in general people who have suffered childhood abuse may have various reasons for not wanting to disclose that information even on an anonymous questionnaire. Again, it is possible that only very honest individuals would admit to such abuse.
Conversely, there is also the possibility that the fantasy prone subjects are reporting incidents of childhood trauma and paranormal experiences which never actually took place in any objective sense. It follows from the definition of fantasy proneness that such individuals would sometimes experience difficulties in source monitoring (Johnson, Hashtroudi, & Lindsay, 1993), confusing events which were only fantasized with reality. Indeed, such issues are at the heart of the current false memory controversy (see, e.g., Loftus, 1993).
I recently carried out a study in collaboration with Michael Kerman (French & Kerman, submitted) which avoided such problems by comparing a group of 23 adolescents who were known victims of childhood trauma, having experienced sexual, physical and/or emotional abuse during their early childhood, with a matched control sample. The adolescents in the abused group were recruited from three adolescent treatment units and those in the control group were recruited from three different schools, in all cases with the consent of relevant ethical committees and the subjects' guardians. The groups were carefully matched on age, sex, verbal intelligence, religion, and ethnic origin. As predicted, the abused group had significantly higher scores on measures of paranormal belief and fantasy proneness. The results of our study, therefore, suggest that conclusions drawn from previous retrospective studies reporting correlations between childhood trauma, fantasy proneness and paranormal belief are in fact valid and this is an avenue which should be explored thoroughly in future research.
There are many types of paranormal claim which I have not addressed in this presentation simply due to time limitations. There are non-paranormal accounts available for every type of paranormal claim you can think of. That does not necessarily mean that the non-paranormal accounts are always right and it is essential that both sides of the debate produce empirical evidence to support their arguments. Several other kinds of paranormal claim will be considered by other members of the panel in presentations today. Many people are convinced that psi is real because of the claims of psychics, from the spoon-bending Uri Geller to psychic detectives, such as Nella Jones and Chris Robinson. As Richard Wiseman will discuss, there are many non-paranormal explanations for such claims which must be ruled out before they can be declared to be genuinely psychic. Susan Blackmore will discuss the strange states of consciousness which may be involved in many types of paranormal experience, from sightings of ghosts to alien abduction claims. Caroline Watt will describe how our inability to estimate probabilities accurately will often lead us to reach for a paranormal explanation when, in fact, coincidence is a quite adequate explanation. Deborah Delanoy and Robert Morris will both consider the area which has the greatest potential for convincing doubters such as myself that there really might be something in paranormal claims which cannot be explained away; that area is experimental parapsychology.
Apart from being of interest in its own right, does this area of study have any wider significance? It is very easy, for scientists in particular, to dismiss paranormal beliefs as trivial and not worthy of serious consideration. I believe that this would be a serious mistake. Paranormal beliefs are found in various forms in all cultures of the world. They are clearly of universal importance to human beings. It may be that psychic forces really do exist. Proof of this would be the most momentous discovery ever. Or it may be, to put it crudely, that paranormal experiences are nothing more than our minds playing tricks on us. I doubt that the types of cognitive bias that I have been discussing will offer anything like a complete explanation for the development and maintenance of paranormal beliefs, but they may be an important component. Why should these biases have developed in the first place? Surely it would be better in evolutionary terms if our cognitive systems were not prone to such biases at all? The universality of the biases suggests, on the contrary, that they in fact bestow some advantage upon the human species in terms of our survival. A cognitive system which is quick and usually right is probably of more value than one which is much slower but right slightly more often.
If such speculations are correct then the study of the biases underlying paranormal beliefs, possibly the greatest of all cognitive illusions, could help to cast considerable light upon the true nature of our species.
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