Read How We Know What Isn't So Online
Authors: Thomas Gilovich
Tags: #Psychology, #Developmental, #Child, #Social Psychology, #Personality, #Self-Help, #Personal Growth, #General
Numerous surveys have asked people to explain the origin of their belief in the paranormal, and all of them point to the importance of personal experience. Forty-one percent of the believers in a sample of Canadian undergraduates cited personal experience, or that of their friends and relatives, as the most important determinant of their belief,
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as did 51% of the believers in a sample of readers of the British journal
New Scientist
.
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Personal experience was also cited as the primary cause of belief by 71% of a sample of members of the Parapsychological Association.
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Clearly, personal experience plays an important role in people’s views of ESP. What type of personal experience do people have in mind, and how is it construed, or misconstrued, as evidence of psi?
Mundane Psychokinesis.
Given the widespread use of various randomizing devices in many gambling and board games, I am convinced that one of the most common (and for many people the earliest) apparent experiences of psi involves attempts to influence such random processes. Nearly everyone has played Monopoly, and who hasn’t tried to “will” the dice to produce whatever numbers are needed to avoid the double hotels lurking ominously on Boardwalk? Occasionally, of course, whatever numbers one attempts to produce do come up. The question is how these successes are interpreted. Is there any reason to expect that they will be construed not as the occasional hits one can expect by chance, but as the product of paranormal powers?
First of all, because psychic powers and the ability to harness them are considered so mysterious, the door is open to selective encoding of success and failure. A hit may be thought to reflect the operation of one’s psychic influence, whereas a miss may be considered nothing but one’s inability to summon one’s influence at that moment. This is reminiscent of the water witcher who only counted his hits in his success rate because “obviously, when I fail, the powers aren’t working at that time, and, after all, I’m counting percentage on the cases where I’m divining, not when I’m just guessing.”
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In addition, there are surprisingly many occasions when, just by chance, a random process produces numerous heads, sixes, or face cards in succession. As we saw in Chapter 2, people have a difficult time accepting the randomness of such streaks. They may thus walk away from the experience of these runs convinced that they have witnessed the operation of some special power.
Everyday Coincidence.
Another phenomenon which tempts many people to speculate about a transcendent force is the experience of a remarkable coincidence. Two friends who have not seen each other in years sit in adjacent seats in a theatre in a foreign town A man dials a wrong number in a distant city, and the recipient turns out to be his college roommate. A woman is thinking about an event she has not thought of in years and intends to discuss it with her spouse; miraculously, he brings it up first. These events seem so improbable, and often produce such powerful emotion, that they strike many people as more than just coincidence.
But how improbable are such events? Many coincidences that seem extraordinary are in reality quite common. The “birthday problem” discussed in many statistics courses is a good example. When asked to consider the probability that at least two people in a group of a particular size were born on the same day of the year, most people are shocked to learn that the odds are roughly 50-50 when the group is as small as 23. More shocking still is that the probability of a matching birthday is 85% when the group size is only 35. Thus, many people will be surprised by an outcome (a pair of matching birthdays) that is not unusual at all.
To the skeptic, all seemingly bizarre coincidences are not terribly amazing when considered from the appropriate statistical perspective. This may be what Aristotle had in mind when he said that “the improbable is extremely probable.” Unlike the birthday problem, however, the exact probability of many coincidental events cannot always be determined. Rough approximations can nevertheless be attempted. A telling example is provided by physicist and Nobel laureate Luis Alvarez, who was struck by a remarkable coincidence in his own life. After reading a brief passage in a newspaper. Alvarez began a series of associations that led him to think of a long-forgotten acquaintance from his college years. Turning the pages of the paper, he was amazed to see an obituary of that very same individual!
Could Alvarez somehow have learned of this person’s death through some non-sensory channel? Or might his recollection of this long-forgotten acquaintance been produced by a precognitive awareness of the obituary itself? Believing such paranormal explanations implausible, Alvarez proceeded to compute an approximate probability of such a coincidence by estimating the number of people the average person knows and how often the average person has such recollections. After making what appear to be reasonably conservative assumptions, Alvarez calculated that the probability of thinking of an acquaintance roughly five minutes before learning of that person’s death is roughly 3 × 10−5 per year. Thus, with the population of the United States as it is, we can expect there to be over 3,000 of these events every year, or almost 10 every day.
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Although Alvarez’s figures are not definitive, they nevertheless fit nicely with the results of the birthday problem, and they remind us that many coincidental events are far less remarkable than they seem. Our misguided intuitions about the true likelihood of such events appear to stem from two sources—a failure to appreciate how often we “sample” from the population of all events, and a reluctance to consider how many
different
events we would consider to be coincidental.
Given the vastness of our experience (how many thoughts we have, how many people we come in contact with, etc.) numerous coincidental events are bound to happen in a lifetime. As Stephen Jay Gould has said, “… time converts the improbable to the inevitable—give me a million years and I’ll flip a hundred heads in a row more than once.”
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People fail to appreciate how many chances they have to experience something coincidental. Perhaps the key to this shortcoming of human intuition is that, unlike coin nipping, the repeated sampling is not obvious because it is not the
same distribution
being repeatedly sampled. By meeting a person here, thinking of someone there, receiving a phone call somewhere else, we are sampling from
different
distributions, and it is this difference that masks the repetitive element of the sampling process. Furthermore, people may be reluctant to think of their own experience, with all its attendant emotions, as a sample from a population of all possible experiences.
Our intuitions about coincidental events also suffer from the problem of “multiple endpoints” discussed in Chapter 4. While the odds of a
particular
coincidence may indeed be vanishingly low, the odds of any of a set of equally remarkable coincidences is generally much higher. Suppose an amateur thespian takes in the theatre while visiting London and runs into his high school drama: teacher. An amazing coincidence to be sure. But would it be any less amazing if it had been his high school co-star? Or his understudy? And suppose it wasn’t London, but Athens, Paris, or Rome? Or what if the encounter had taken place, not in the theatre, but at the opera house, a museum, or even a pub?
By pulling back a bit like this, we quickly see that although the probability of any one coincidence is indeed quite low, the probability of the
union
of all such coincidental events can be quite high. Our sense of astonishment when confronted by coincidence can thus be traced to our intuitive tendency to assess the likelihood of the
intersection
of the specific events that did occur, rather than the union of all similar outcomes that might have occurred. The birthday problem is instructive in this regard. Many people approach the problem with a fairly accurate sense of the long odds against a
particular
pair of people having the same birthdate (approximately 1/365), but they fail to appreciate how many different pairs of people there are (253) in a group of 23.
Finally, people may be inclined to see some sort of guiding hand behind many coincidental events because of the powerful emotions these experiences often produce. Because “big” events are thought to require “big” causes (see ch. 2), purely-random coincidence is considered by many to be an unacceptable explanation of such a compelling and evocative occurrence.
Everyday Premonitions.
Premonitions tend to elicit paranormal explanations as much or more as a startling coincidence. In fact, premonitions are really a special class of coincidence—a coincidence between a person’s thoughts and events in the outside world. Someone dreams about a plane crash and then hears about precisely that event on the evening news. Someone reminisces about an old acquaintance, and the acquaintance suddenly walks in the room.
Premonitions strike people as compelling for the same reason that underlies the impact of coincidence—they seem too improbable to occur by chance. But given how often an active mind thinks of people, places, and events, the briefest reflection informs us that a person is almost certain to experience quite a few premonitions in a full lifetime. Death, for example, is a very frequent topic of dreams, and so it is hardly surprising if one such dream should happen to correspond to a real-world fatality. That does not make a person’s premonitions of death terribly meaningful or informative, however. One is reminded here of economist Paul Samuelson’s crack that the stock market has accurately predicted nine of the last five recessions.
Premonitions are also precisely the kind of “one-sided” events (chapter 4) for which the successes stand out and the failures go unrecognized. People daydream about long-lost friends all the time, but little of the specific content of such reveries can generally be recalled—unless they should happen to be followed by an unexpected visit by that very same person. Against this background of selective recall, any one premonition looms as a much more impressive event than it really is. Francis Bacon noted this long ago when he said that “… all superstition is much the same whether it be that of astrology, dreams, omens, retributive judgment, or the like, … [in that] the deluded believers observe events which are fulfilled, but neglect or pass over their failure, though it be much more common.”
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Another curious feature of premonitions that makes them more likely to happen is that they often occur after the fact. A man has a vague, unpleasant dream about riding in a plane that is out of control (or was it a boat?), and the morning paper carries the story of a fiery plane crash. This can be a striking experience to be sure, but how much of the recollection of the dream was shaped by the details of the next day’s news? Dreams are particularly suspect in this regard because their multi-faceted, kaleidoscopic nature makes them something of a “one size fits all” premonition that is easy to fulfill. Psychologist James Alcock cites intriguing evidence of the retrospective nature of many prophetic dreams: Those who claim to have such experiences report that their prophetic quality disappears after he has them record their dreams!
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Retrospective prophecies, if you will excuse the oxymoron, are so successful because they capitalize on multiple endpoints, a problem that plagues not only dream prophecies but those produced by conscious minds as well. Some prophecies are so vague that they can be “fulfilled” by almost any outcome. Those offered by that resurgent seer Nostradamus are a case in point. Although not quite as vacuous as those in Woody Allen’s spoof of the sixteenth-century astrologer-physician (“Two countries will go to war, but only one will win”),
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his prophecies are so vague and difficult to interpret that it is hard to imagine how they could be disconfirmed. His popularity is thus truly baffling, particularly when one learns that he essentially made this admission about his predictions himself! He stated that he phrased his prohecies in such a way that “… they could not possibly be understood till they were interpreted after the event and by it.”
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People can also be unduly impressed by premonitions by failing to identify the operation of subtle causal factors that produced them. Suppose that after visiting a relative you depart with a vague sense of unease: Your relative looks “different” in a way that you cannot quite identify. This unease leads to anxious dreams about the person, perhaps one in which he or she is harmed. Suppose, in addition, that two days later you learn that this same relative has been hospitalized with a serious ailment. Under these circumstances, it is hard to resist the conclusion that you have forseen this bad turn of events—you have. But what is the cause of the premonition? Unfortunately, many people leap to a paranormal explanation, and miss completely how their initial unease was both a cause of their dream and a reflection of the ill health that led to the relative’s hospitalization.
Telephone calls that occur “out of the blue” by the target of one’s ruminations also have this quality. A rumination about a particular person may be triggered by some external event with which he or she is associated. That same external event, of course, can lead that same person to think about you and thus prompt a phone call. Because these associations can occur at a less than fully conscious level, there may be no obvious cause of the call, making one’s thoughts appear to be truly psychic.
Extraordinary Premonitions.
Putting aside all of these elements that make many astonishing premonitions much less than that in reality, there nevertheless are occasions in which people experience clear, precise foreshadowings of significant events that do in fact occur exactly as forseen. Here again, though, the important question is whether they occur more frequently than one would expect by chance. The notion that it is just coincidence may be difficult to accept for anyone who has had such a premonition and experienced all the powerful emotion and sense of awe they inspire. Intuitively, such awesome events demand more than mundane causes—certainly more than the implication that there is no cause at all. Furthermore, because these kinds of premonitions involve events like illness and death that we associate with the transcendent, it is only a small cognitive step to a transcendent explanation like ESP.