How We Know What Isn't So (30 page)

Belief in ESP has been remarkably unaffected by the consensus of the scientific community that there is no “scientific justification for the existence of [such] phenomena.”
⁴⁰
Are there any factors other than the misconstrual of everyday experience, the will to believe, and exposure to pro-ESP media accounts, that can help explain the robustness of these beliefs? Here it may be important to focus particularly on the beliefs of that abstract entity, the “intelligent layperson,” who is likely to be at least vaguely aware of the scientific skepticism about ESP and yet is not as psychologically invested in this issue as, say, a parapsychologist.

People generally believe the scientific community, even when it makes claims that seem bizarre or that conflict with the apparent lessons of everyday experience. Few quarrel with the claim that the earth is round or that it revolves around the sun, despite immediate experience that seems to suggest otherwise. People also readily accept the existence of quarks, black holes, and gaps in the ozone layer—entities that can be difficult to fathom. Why is the word of science accepted in these cases, but not with respect to ESP?

Part of the answer lies in the nature of the skeptical perspective on ESP. To say that ESP does not exist is to take something away from a person. Exciting phenomena either have one of several mundane explanations or they simply do not exist. Thus, the skeptic asks that what seems to be a unified—although not terribly deep—explanation of a host of phenomena (i.e., that psychic powers exist) be replaced by a patchwork of explanations or no explanation at all. The skeptical perspective, therefore, may sometimes be rejected because it can appear to lack elegance: A single explanation (ESP in this case), by the sheer force of its diversity, generally appears more plausible than a set of disjoint accounts. People act much like professional scientists who are willing to tolerate troublesome data in allegiance to a unifying theory—until a more elegant and unified theory is discovered.
⁴¹
The skeptical perspective on ESP, although driven by the pertinent data, does not provide such unity or elegance.

Note that people’s discomfort with the absence of a unified theory can serve to subtly shift the burden of proof about ESP to where it does not belong—to the skeptic. Logicians and philosophers are in virtual unanimous agreement that the burden of proof on any question lies not with the skeptic, but with the person making the positive assertion. The tables are often turned in discussions of ESP, however. Because psi serves as the default explanation of seemingly paranormal events, the skeptic is often asked to specify “if it wasn’t ESP, what was it?” How, in other words, can a particular anomaly be explained without ESP? But to claim that “if not this, it must be that” is to commit a logical fallacy. The failure to supply a convincing “natural” explanation for an anomalous event may be more a reflection of the limits of our knowledge than an argument for psi.

The Tenacious Beliefs of Parapsychologists.
The debate about ESP is generally framed as a question of how likely it is that psi exists, given the evidence of everyday life and the parapsychology laboratory. Skeptics and parapsychologists obviously differ in their assessments of this likelihood. Another way to frame the debate, however, is to ask, “if psi existed, and a research program were conducted to examine it, what would we expect to discover?” Although this may seem like a mere semantic trifle, it focuses attention on some potentially informative questions. For instance, what would those who started the scientific investigation of psi have expected to result from 130 years of research? The answer is of course impossible to know with certainty, but it is hard to resist the conclusion that they would have been disappointed with what has been obtained thus far. After all, what regular phenomena has this research uncovered? There is the “experimenter effect,” whereby positive results are obtained by sympathetic investigators and inhibited by skeptics. There is the “decline effect,” whereby the psi powers of even the most gifted subjects decline and generally disappear over time. And there is “psi-missing,” whereby gifted subjects sometimes reveal their powers of apprehending concealed targets by making significantly
fewer
correct responses than expected by chance.

If psi existed, is it likely that this is what we would have to show for 130 years of continuous investigation? To be fair, others might quarrel with my characterization of what are the consistent findings of parapsychological research, and they may want to include additional results. But even with a more generous inclusion of a few additional findings, the overall assessment remains much the same. When the debate is framed in this way, in other words, it becomes clear that the acceptance of ESP represents a classic case of people’s beliefs surviving the challenge of disconfirmation at the hands of the relevant evidence.

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It could be argued that few experiments with absolutely no flaws are ever performed, and that scientists nearly always draw conclusions from a pattern of data obtained from variously flawed studies. It is important to point out, however, that scientists only feel comfortable basing conclusions on the results of a series of flawed studies if the flaws are varied and compensatory. Indeed, successive studies are explicitly designed to rule out the problems with earlier experiments, and in so doing they often eliminate one shortcoming and create another. The successive studies, then, are not all subject to one or more of a small number of flaws. This is not true of the research on the portacaval shunt, in which the flawed studies all suffered from the lack of random assignment of patients to treatment conditions.

*
This research, for which the controls were in fact less than adequate, was conducted at Stanford Research Institute. The institute is not affiliated with Stanford University. A summary of the methodological flaws of this research can be found in J. Randi (1986)
Flim-Flam
. Buffalo, NY: Prometheus Books.

*
This is not meant to be an exhaustive review of the history of research on ESP. I attempt only to provide an overview of some of the most well-known and widely-cited studies in the field, and to discuss the problems associated with those studies. For the reader interested in obtaining a more complete review, an useful introduction may be obtained by reading the exchange between believers and skeptics in
Behavioral and Brain Sciences
, 1987, vol. 10, pp. 539-643.

*
In the typical ganzfeld experiment, the percipient is put into a state of mild sensory deprivation (halved ping-pong balls are placed over the eyes and “white noise” is heard through a set of earphones). He or she then tries to report on the images being “sent” by someone in another room. In the typical psychokinetic study, a machine randomly selects which of a set of four lamps is lit on a given trial. The participant’s task is to try to mentally influence the randomizing device to produce one particular outcome. As mentioned above, these two research paradigms are considered by many investigators to be the most promising in the field of parapsychology. Skeptics remain unconvinced, however, and they cite a number of procedural and statistical artifacts that could account for the results. [See R. Hyman, (1985). The ganzfeld/psi experiment: A critical appraisal.
Journal of Parapsychology
,
49
, 3-49; R. Hyman & C. Honorton (1986). A joint communique: The psi ganzfeld controversy.
Journal of Parapsychology
,
50
, 351-64; R. Hyman (1981). Further comments on Schmidt’s PK experiments.
Skeptical Inquirer
,
5
, 34-40.] None of these artifacts seem as definitive on the surface as those associated with the efforts of Rhine, Soal, or Targ and Puthoff, making the lack of replicability by independent investigators their most serious current shortcoming.

M
any treatment strategies and training efforts are designed to eliminate the source of the existing problem. When someone has an infection, for example, the underlying cause can be treated by administering antibiotics. When someone first learns to drive a car with a manual transmission, problems often arise from the predisposition to let out the clutch prematurely. With practice, however, the person gradually learns to let it out at the appropriate rate and the initial tendency to rush things simply disappears.

There are other times, however, when the source of the problem cannot be eliminated, and so it must be counteracted. We do not cure nearsightedness; we prescribe corrective lenses. We do not eliminate the urge to eat in people who are overweight; we prescribe diet and exercise regimens to achieve a balance between caloric intake and output. When we teach ethics to our children, we are unlikely to eradicate fully their basic self-centeredness; instead, we counteract it by instilling compensatory moral principles—“Do unto others as you would have them do unto you,” “What goes around, comes around,” or “What would happen if everyone were to do what you did?”

When we turn to the question of what can be done to improve everyday reasoning and to spare us from the kinds of questionable and erroneous beliefs discussed in this book, it should be clear that it is the latter, compensatory strategy that is required. The underlying causes of faulty reasoning and erroneous beliefs will never be eliminated. People will always prefer black-and-white over shades of grey, and so there will always be the temptation to hold overly-simplified beliefs and to hold them with excessive confidence. People will always be tempted by the idea that everything that happens to them is controllable. Likewise, the tendency to impute structure and coherence to purely random patterns is wired deep into our cognitive machinery, and it is unlikely to ever be completely eliminated. The tendency to be more impressed by what
has
happened than by what has
failed
to happen, and the temptation to draw conclusions from what
has
occurred under present circumstances without comparing it to what would have occurred under alternative circumstances, seem to be similarly ingrained.

These underlying causes of erroneous beliefs will never simply disappear. They must, then, be held in check by compensatory mental habits that promote more sound reasoning. To avoid erroneous beliefs, in other words, it is necessary that we develop certain habits of mind that can shore up various deficiencies in our everyday inferential abilities.

Fortunately, there is reason to believe that these corrective habits of mind are not difficult to develop. Students who are familiar with the recent work on the errors and biases of human judgment seem able to apply the lessons of this research to their everyday lives. I have occasionally overheard my own students remark to their peers, “Yeah, but what do the other three cells look like?”, “But we all know that people will see order in almost anything—isn’t this just like the hot hand?”, or “Remember, though, we’ve only heard about this secondhand.” The necessary principles appear to be easy to understand and to learn; the critical task is to get them so firmly entrenched that they are readily applied to everyday life.

What are these essential habits of mind, and how can we develop them? To a large extent, they have already been discussed implicitly in earlier chapters. To specify the mechanisms that give rise to erroneous beliefs is to tacitly identify what is necessary to prevent them. Any analysis of a specific type of faulty reasoning implies a strategy for improvement. Given the contents of earlier chapters, then, here it is perhaps best if we only briefly consider some of the habits of mind that are most important to cultivate.
*

Perhaps the most general and most important mental habit to instill is an appreciation of the folly of trying to draw conclusions from incomplete and unrepresentative evidence. An essential corrollary of this appreciation should be an awareness of how often our everyday experience presents us with biased samples of information. Rather than being overly impressed with the evidence immediately before us, we need to step back and ask, like the perspicacious graduate student mentioned above, “What do the other three cells look like?” Theists, for example, note the number of times their prayers have been answered and conclude that there is a benevolent god; atheists cite the occasions that their prayers have gone unanswered and conclude that we are on our own. Both need to develop the habit of thinking more broadly. Both must consider the number of times their hopes have been realized when they have prayed and when they have not, as well the number of times their hopes have been dashed when they have prayed and when they have not.

As we have seen many times throughout this book, not all of these four types of information are equally likely to come to one’s attention, and so it is important to be particularly energetic in trying to dig up the most elusive information. We need to be aware, for example, of how often our role, status, or position in a social network can cut us off from certain classes of informative data. Clinicians should temper their conclusions about the prognosis and essential treatment of certain pathologies by considering how people who are not in therapy deal with the condition in question. Admissions officials should modulate their assessments of their ability to discriminate between qualified and unqualified applicants by considering how well the people they turned down would have performed had they been accepted. Before drawing firm conclusions, in other words, we need to ask ourselves whether there are any “invisible” data we may be overlooking.