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In parapsychology, precognition (from the Latin præ-, “before,” + cognitio, “acquiring knowledge”), also called future sight, and second sight, is a type of extrasensory perception that would involve the acquisition or effect of future information that cannot be deduced from presently available and normally acquired sense-based information or laws of physics and/or nature. A premonition (from the Latin praemonēre) and a presentiment are information about future events that is perceived as emotion.
The existence of precognition, as with other forms of extrasensory perception, is not accepted as other than a purely psychological process by the mainstream scientific community because no replicable demonstration, "on demand", has ever been achieved.[verification needed]
Scientific investigation of extrasensory perception (ESP) is complicated by the definition which implies that the phenomena go against established principles of science. Specifically, precognition would violate the principle that an effect cannot occur before its cause. However, there are established biases, affecting human memory and judgment of probability, that create convincing but false impressions of precognition.
Many of the "psychic experiences" that are volunteered to parapsychologists by the general population involve apparent precognition. In one review of a U.S. case collection, submitted to Duke University's Parapsychology Laboratory, 75% of 1777 dream-based experiences were of an ostensibly precognitive type, as were 60% of 1513 wakeful experiences. A similar pattern was identified for a separate collection of 157 cases experienced by children; here, the largest category of experiences was again of precognitive dreams (52%), followed by precognitive intuitions (52%). A German case collection produced a similar figure: 52% of 1,000 cases were of the apparently precognitive type. A British study of 300 volunteered cases showed 34% to be apparently precognitive.
History records many instances of apparent precognition (see Ides of March), and belief in its occurrence as a form of seeing into the future (this can be through visions, déjà vu or through dreams which is usually the cause of recognition). The first thorough collection and critical review of such spontaneous cases was created by the British Society for Psychical Research (SPR). Reports of these cases were authored by Eleanor Sidgwick in 1888, and Herbert Saltmarsh in 1938. Sidgwick believed the evidence warranted further investigation as to the validity of the concept of precognition, and Saltmarsh offered that the evidence, if it did not scientifically establish the phenomenon, at least excluded alternative hypotheses. Nicol, however, in a later review, came to the conclusion that their evidence was not so suggestive, given, in particular, the long length of time between the occurrence of some of the most suggestive cases, and their first report to the SPR.
J. W. Dunne, a British aeronautics engineer, recorded each of his dreams as they occurred to him, identifying any correspondences between his future experiences and his recorded dreams. In 1927, he reported his findings, together with a theory, in An Experiment with Time. In this work, at least 10% of his dreams appeared to represent some future event, pertaining to some relatively trivial incident in Dunne's own life, or some major news events appearing in the press a day or so after the dream. Dunne concluded that precognitive dreams are common occurrences: many people have them without realizing it, largely because they do not recall the details of the dream. Also reported in the book was an experiment Dunne conducted with several other people who studiously recorded their dreams and sought to associate them with subsequent experiences. Dunne felt these confirmed his theory, but a 1933 independent experiment failed to replicate his findings.
With free-response methods, experiments have been conducted in precognitive dreaming at the sleep laboratory of the Maimonides Medical Center, in precognitive Ganzfeld hallucinations and visions. While such experiments have produced some suggestive evidence for precognition, they have been somewhat limited to studies of selected participants, and have involved procedures that can be too expensive for other researchers to replicate, or too complex to theoretically interpret.
Most experiments on precognition have involved a forced-choice procedure. The first such ongoing and organized research program on precognition was instituted by J. B. Rhine in the 1930s at Duke University's Parapsychology Laboratory. Rhine used a method of forced-choice matching in which participants recorded their guesses as to the order of a deck of 25 cards, each five of which bore one of five geometrical symbols. The test of precognition was based on the fact that these "guesses" were made before the deck was shuffled by the experimenter. In an effort to distinguish between different parapsychological accounts of precognition, and to better understand its conditions, experiments were conducted in which the order of the target deck of cards was determined by hand versus machine, or by reference to macroscopic events, such as randomly selected meteorological readings, or by complex algorithms. Early experiments also sought to determine the temporal scope of precognition by organizing the target deck only 1-2 versus 10 days, or even a year, after responses had been recorded and secured.
Experiments by Samuel G. Soal, a mathematician, and colleagues seemed to provide impressive evidence of precognition. They ran forced-choice ESP experiments in which someone attempted to identify which of five animal pictures a subject in another room was looking at. Their performance on this task was at chance, but when the scores were matched with the card that came after the target card, three of the thirteen subjects showed a very high hit rate. These experiments were hailed as "the most impressive data ever reported" for ESP, with controls that "seem to be absolutely watertight". Rhine described Soal's work as "a milestone in the field". A dissenting view came from research chemist George Price who reviewed Soal and Bateman's book Modern Experiments in Telepathy for the journal Science in 1955. Price argued that since ESP was so unlikely, the positive results not attributable to error were more likely the result of deliberate fraud. This prompted several replies that Price's criticism was unfair, resting on the mere possibility of fraud rather than actual proof. In 1978, the experiments were in fact exposed as totally fraudulent. The statistician and paragnost Betty Markwick, while seeking to vindicate Soal, discovered that he had altered his data to create all the extra hits and give the study its statistical significance. The untainted experimental results showed absolutely no evidence of precognition in the hits or the ratios.
A meta-analysis of all reports in the parapsychological literature of card-calling experiments on precognition was conducted in the late 1980s. This encompassed 309 experiments reported by 62 different investigators and published between 1935 and 1987. 23 of the 62 investigators reported positive results. The overall result offered precognition as a reliable but small effect over these studies, and an effect that could not be accounted for by levels of methodological reliability (as assessed by rating the studies on eight attributes of method), nor any publication bias against reporting null results.
Other researchers, including Smithsonian Executive Secretary Charles Greeley Abbot and British psychologist R. H. Thouless, introduced the study of precognition in the displacement of guesses to targets. This involved a set of target symbols, and "guesses" as to their identity, but, rather than precognizing the order of a whole deck of symbols, scored for precognition by checking the correspondence between each response and the target assigned to one or more trials ahead of that to which the response was originally assigned. Several studies using this method have continually offered displacement as reliable evidence for precognition.
Following these experiments, a more automated technique of experimentation was introduced that did not rely on hand-scoring of equivalence between targets and guesses, and in which the targets could be more reliably and readily tested as random. This involved testing for precognition with the use of high-speed random event generators (REG), as introduced by Helmut Schmidt in 1969 and further conducted, in particular, at the Princeton Engineering Anomalies Research Lab (1979–2007). In this procedure, participants indicate when they believe (by whatever means available to them) that the REG has produced an event that either conforms or differs from one of two target events. In comparison to the card-guessing type of experiments, this procedure permits much more data to be collected in an experimental session, while reducing the number of alternatives that need to guessed.
Another class of experiments have tested for precognition by unconscious signs. These have involved physiological responses, such as of skin conductance and electroencephalographic activity, or indirect psychological measures, such as ratings of preference for one or another target alternative. In these experiments, participants are not asked about their experiences, and do not need to be informed that they are participating in an experiment on ESP. Dick Bierman and Dean Radin have reported positive evidence of precognition in experiments of these kinds.
Various psychological processes have been offered to explain experiences of apparent precognition.
Suited to explaining at least naturalistic occurrences of apparent precognition are several more or less hypothetical unconscious cognitive processes. These include:
Some psychologists have explained the apparent prevalence of precognitive dreams in terms of memory biases, namely a selective memory for accurate predictions and distorted memory so that dreams are retrospectively fitted onto subsequent events. In one experiment, subjects were asked to write down their dreams in a diary. This prevented the selective memory effect, and the dreams no longer seemed accurate about the future. Another experiment gave subjects a fake diary of a student with apparently precognitive dreams. This diary described events from the person's life, as well as some predictive dreams and some non-predictive dreams. When subjects were asked to recall the dreams they had read, they remembered more of the successful predictions than unsuccessful ones.
There are several ways by which precognition can be conceived as occurring without fundamental dependence on normally recognized processes of perception and cognition, i.e., by psi.
Firstly, there are several ways to explain precognition as a form of extrasensory perception. Precognition can be conceived as an extraordinary process of clairvoyance, involving no direct perception of the future. If, as is offered by the philosophy of determinism, all future events are determined by present conditions, then it can be suggested that it is clairvoyance of all the relevant present conditions that permits one to know their future outcomes. Alternatively, if somebody in the present is aware of what will happen in the future, then it can be suggested that it is telepathy of that information that grants oneself a like knowledge of the future. "Seeing into the future" can also be conceived as not a direct perception of a future event, but only a perception of one's own future experience of that event; what J. B. Rhine called precognitive sensory perception. Support to this suggestion is given by the meta-analysis which includes the study of a subset of experiments in which details were provided about the feedback of target information given to subjects in the future. The study shows that when no feedback was given, the significance of the results fell to chance-expectation. This does suggest that the contacts were being made with the subject's future experience of receiving the target information, and not with the targets themselves.
The construct of psychokinesis permits another set of ways to think about precognition. It can be suggested that precognition involves the influence of present conditions so that they conform with what is precognized. Alternatively, a retrocausal process can be proferred as an explanation, raising the idea that, at a future time, the ostensibly present conditions are influenced backward in time.
As for theories of precognition itself, parapsychologists have offered several phenomenological theories that – like most psychological theories themselves – do not presume to provide a physical explanation of how precognition occurs, but only seek to describe the processes that must, it seems, be occurring at a psychological level of explanation. There are two classes of such theories, which are not exclusive to each other.
One class of theories – principally as discussed, albeit in quite disparate ways, by Dunne (1927) and Saltmarsh (1938) – supposes that awareness is fundamentally trans-temporal, acquiring information beyond the "specious present" of information that is typically available for immediate awareness. While we are only ever consciously aware of some limited temporal range of information, these theories assert that, unconsciously, a much wider temporal range of information is sampled and used for the benefit of the organism.
Influenced by Gerald Feinberg's concept of a tachyon, some parapsychologists such as Martin Ruderfer (1974) theorised that tachyons can travel backwards in time and may be able to explain cases of precognition. The British physicist and mathematician Adrian Dobbs (1965) proposed a theory in which precognition occurs due to “psitrons,” hypothetical particles similar to tachyons that travel backward in time which may contact an observer's brain to produce a precognitive experience. The major problem with the tachyon theory of precognition is that tachyons have never been observed to exist; they remain theoretical constructs. Arthur Koestler discussed the theory of Dobbs in his book The Roots of Coincidence.
This theory, offered by then psychologist Rex G. Stanford, proposes that humans unconsciously and automatically scan their environment for motivationally relevant information, including - as the subliminal awareness models suggest - information that will only occur in the future of each conscious observer. This information will be used, by those who are so disposed, to place the person in a goal-relevant position with respect to its environment. This creates the experience of precognition, should some of this information have been represented in conscious imagery or other representational forms.
One class of parapsychological theories makes reference to the measurement problem in quantum mechanics, particularly as it implicates the constructive role of human observation. Precognition, in the context of these theories, is generally conceived in the manner of retroactive psychokinesis, but without recourse to any notion of the transmission of psychophysical energy. According to some observational theories, it is at the point of observation of a future event that the event is, in fact, determined, and, under certain conditions of motivation, randomness and feedback, this future observation can inform the present observer.
Another class of theories is based on the block universe model, in which future events already exist in spacetime, according to the special theory of relativity. The theories explain precognition as the retrieval of memories from the brain in the future, which could occur in a similar way to that in which ordinary memories are retrieved from the brain in the past.
The theory proposed by Jon Taylor is based on David Bohm's theory of the implicate order, which suggests that if similar structures are created at different places and different times, the structures resonate with a tendency to become more closely similar to one another. Taylor applies the principles to the neuronal spatiotemporal patterns that are activated in the brain, to show how an information transfer could be produced. For example, a precognition would occur when the pattern activated at the time of the future experience of an event resonates with any similar pattern that is spontaneously activated in the present. This might enable the present activation to be sustained until it produces the conscious awareness of an event similar to the one that will be experienced in the future.
The experimental research into ostensible precognition has, like much of the research into extrasensory perception, been subject to various critiques of its methodology. This concerns the fundamental logic of the methods, and particular aspects of procedure. A general issue is concerned with the possibility that the phenomena contradict generally recognized principles of science, coupled with the absence of a method to demonstrate precognition on demand.
Louisa Rhine at the Parapsychology Laboratory at Duke University compiled the best-known and largest body of dream evidence. Dr. Rhine collected over 7000 accounts of ESP experiences. The majority of these accounts were dream related and were seemingly precognitive in nature. The material for this work was collected by advertisements in various well-known popular media.
David Ryback, a psychologist in Atlanta, used a questionnaire survey approach to investigate precognitive dreaming in college students. His survey of over 433 participants showed that 290 or 66.9 percent reported some form of paranormal dream. He rejected many of these claims and reached a conclusion that 8.8 percent of the population was having actual precognitive dreams.
An early inquiry into this phenomenon was done by Aristotle in his On Divination in Sleep. His criticism of these claims appeals to the fact that "the sender of such dreams should be God", and "the fact that those to whom he sends them are not the best and wisest, but merely commonplace persons." Thus: "Most [so-called prophetic] dreams are, however, to be classed as mere coincidences...", here "coincidence" being defined by Aristotle as that which does not take "place according to a universal or general rule" and referring to things which are not of themselves by necessity causally connected. His example being taking a walk during an eclipse, neither the walk nor the eclipse being apparently causally connected and so only by "coincidence" do they occur simultaneously.
Other researchers in this area are more guarded in their reports on the value or use of dreams. In his book The Interpretation of Dreams, first published at the end of the 19th century, Sigmund Freud argued that the foundation of all dream content is the fulfillment of wishes, conscious or not and devoid of psychic content. On the other hand, Freud's view of precognition evolved. According to Jung, Freud's "materialistic prejudice" and "shallow positivism" lead him to reject the entire complex of questions relating to precognition and the occult as "nonsensical." But years later, adds Jung, Freud both "recognized the seriousness of parapsychology and acknowledged the factuality of 'occult' phenomena."
Dreams which appear to be precognitive may in fact be the result of the "Law of Large Numbers". Robert Todd Carroll, author of "The Skeptic's Dictionary" put it this way: "Say the odds are a million to one that when a person has a dream of an airplane crash, there is an airplane crash the next day. With 6 billion people having an average of 250 dream themes each per night, there should be about 1.5 million people a day who have dreams that seem clairvoyant."
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