Superstition Masquerading as Science

Dean McKay, Rachel Ammirati, Scott O. Lilienfeld

An essay by Dr. Richard Gallagher, a psychiatrist who purports to be “a man of science,” was featured in the July 1, 2016, online Opinions section of the Washington Post. The essay elicited strong reactions from many quarters; for example, it has drawn over 2,800 online responses as of this writing. Although the title of Gallagher’s essay is alarming enough—“As a psychiatrist, I diagnose mental illness. Also, I help spot demonic possession”—his grasp of science is even more troubling. In his essay, Gallagher claims to be able to identify individuals who are demonically possessed and to help exorcists distinguish them from people suffering from genuine mental illnesses. As clinical psychologists, two of whom are members of the Public Education and Media Committee of the Society for a Science of Clinical Psychology (SSCP), we are deeply concerned that his approach to explaining human behavior has the potential to damage the profession and contribute to harmful mental health practices.

At the outset, Gallagher tries to persuade readers that he is a skeptic. He describes himself as “inclined to skepticism” and notes that he once told an exorcist, “I wasn’t likely to go in for a lot of hocus pocus.” He argues that “respect for evidence,” among other virtues, guides his approach to psychiatry, teaching, and evaluating claims concerning demonic possession. Further, he asserts, reasonably, that in most cases behaviors attributed to possession can be accounted for by “more prosaic problems” such as “a medical disorder; mental illnesses,” suggestibility, or “fraud.”

Gallagher’s Observations

Nevertheless, Gallagher’s apparent skepticism dissolves once he recounts the story of his first encounter with a woman whom he concluded was possessed by a demon. He describes her as a “self-styled high priestess” who “called herself a witch and dressed the part, with flowing dark clothes and black eye shadow around to her temples.” It is unclear if the woman’s prototypical appearance influenced his conclusion that she was “possessed” (see Tversky and Kahneman 1974 for a discussion of the representativeness heuristic), but almost certainly other elements of her behavior did. Shortly after touting his many Ivy League affiliations (which in science should carry less weight than the ability to think critically and a commitment to basing arguments on high-quality data), Gallagher builds suspense by telling readers that he has witnessed phenomena that he cannot explain using conventional knowledge. He then relates the following observations regarding this woman’s behavior:

She could tell some people their secret weaknesses, such as undue pride. She knew how individuals she’d never known had died, including my mother and her fatal case of ovarian cancer. Six people later vouched to me that, during her exorcisms, they heard her speaking multiple languages, including Latin, completely unfamiliar to her outside her trances.

Logical Problems

There are several serious inferential problems with Gallagher’s arguments (see also Novella 2016 for a critique of Gallagher’s claims). First, “undue pride” is hardly a rare or idiosyncratic weakness. Second, Gallagher neglects to consider the possibility that the woman’s apparently preternatural awareness could merely be the result of cold reading. Cold reading consists of a set of techniques, such as making educated guesses based on population base rates or providing highly generalized descriptions that apply to almost everyone (the P.T. Barnum effect), which are routinely exploited by fortune-tellers, psychics, magicians, and others who wish to persuade people that they possess paranormal abilities (Hyman 1977; Rowland 2001). Third, some of what appears to be evidence of this woman’s psychic abilities could also or alternatively reflect hot reading, that is, obtaining information about a target using nonparanormal means, such as reading newspaper obituaries or searching the Internet. Fourth, the assumption that a person could speak multiple languages only while in a “trance” is dubious at best. Did Gallagher entertain the hypothesis that she simply hadn’t advertised having learned these languages previously? And how do we know that her Latin was especially accurate? Fifth, it is unclear why, given what is widely known about the limits of eyewitness testimony (Arkowitz and Lilienfeld 2009), Gallagher would be so willing to believe the “vouched” reports of a group of eyewitnesses, especially those who are presumably motivated to believe in demonic possession.

The “self-styled high priestess” whom Gallagher discussed reported that she had connections to Satanism, going so far as to identify herself as Satan’s “queen.” Yet the accuracy of her report should be highly suspect given psychological research on memory. For example, laboratory research indicates that individuals who report experiencing past lives (Meyersberg et al. 2009) and alien abductions (Clancy et al. 2002) display higher rates of false recall and commit more recognition errors than do comparison participants.

Gallagher further offers levitation, extreme strength (which can be caused by excess cortisol and adrenaline surging through the bloodstream; Wise 2009), and “statements of astonishing venom and contempt for religion” (which do not require a paranormal explanation) as compelling evidence that demonic possession is real. Without a doubt, evidence of levitation without assistance would be extraordinary; however, we shouldn’t assume it is due to demonic possession. Notably, Gallagher acknowledges that “I have not witnessed a levitation myself, but half a dozen people I work with vow that they’ve seen it in the course of their exorcisms.” Thus, his most impressive ostensible evidence for the existence of demonic possession again relies on secondhand eyewitness testimony. In addition to the great potential for errors in memory, might those who report witnessing levitation be unduly motivated to see it? Might they be misinterpreting another behavior, such as erratic jumping, as levitation? Indeed, Gallagher neglects to note that skeptics have debunked similar apparent episodes of levitation (“yogic flying”) among people practicing transcendental meditation, demonstrating that they reflect little more than unimpressive hops (Carroll 2011). Moreover, when asked why he and others have been unable to produce more compelling evidence of levitation, Gallagher offers an answer that smacks of a common sign of pseudoscience, namely, evasion of peer review: “One cannot force these creatures to undergo lab studies or submit to scientific manipulation; they will also hardly allow themselves to be easily recorded by video equipment, as skeptics sometimes demand.”

Although Gallagher claims to engage in “careful observation of the evidence” related to demonic possession, his conclusions regarding the possibility of being a “sophisticated psychiatrist” who believes in demons reveal his biases:

Most of my scientific colleagues and friends say no, because of their frequent contact with patients who are deluded about demons, their general skepticism of the supernatural, and their commitment to employ only standard, peer-reviewed treatments that do not potentially mislead (a definite risk) or harm vulnerable patients. But careful observation of the evidence presented to me in my career has led me to believe that certain extremely uncommon cases can be explained no other way.

To say that something “can be explained no other way” suggests that Gallagher, a “practicing Catholic” and author of a book about demonic possession, has fallen prey to confirmation bias, the ubiquitous tendency to attend only to evidence that supports one’s beliefs and to neglect evidence that does not (Nickerson 1998). Yet confirmation bias is exactly what the tools of science help us to overcome. Furthermore, it is worrisome that Gallagher seems almost to scoff at the dedication of some mental health providers to using treatments that do not mislead vulnerable patients.

Logical fallacies are also evident in many of Gallagher’s key arguments (see Novella 2016). After noting that many cultures believe in possession and the paranormal, he states, “despite varying interpretations, multiple depictions of the same phenomena in astonishingly consistent ways offer cumulative evidence of their credibility.” Here, Gallagher commits the bandwagon fallacy—the erroneous assumption that widespread belief in a claim constitutes sufficient evidence for it. Or, as psychologists often say, reliability (consistency) should not be confused with validity. His assertions also seem to court the argumentum ad antiquitatem fallacy—the erroneous assumption that a belief must be true because it has existed across long stretches of time. More likely, the fact that belief in the paranormal has been “astonishingly consistent” across cultures says more about the nature of human cognition (i.e., that there is something about the brain that renders us susceptible to supernatural beliefs) than about the existence of demons. Later, Gallagher commits the logical fallacy of false equivalence—assuming that two things are the same when in fact they are not—when comparing evidence for demonic possession to evidence for George Washington’s crossing of the Delaware. He contends that “in both cases, written historical accounts with numerous sound witnesses testify to their accuracy.” Perhaps had historians claimed that George Washington levitated across the Delaware, Gallagher’s comparison might be defensible. Yet even if this hypothetical scenario were true, it would not change the fact that Gallagher is again relying on anecdotal testimony.

After initially advertising his “skeptical” approach to evaluating claims of possession, Gallagher commits the common error of confusing skepticism with cynicism. He states, “while the American Psychiatric Association has no official opinion on these affairs, the field (like society at large) is full of unpersuadable skeptics and occasionally doctrinaire materialists who are often oddly vitriolic in their opposition to all things spiritual.” Unwillingness to entertain a remarkable claim (cynicism) differs greatly from demanding evidence that is as remarkable as the claim (skepticism). A skeptical thinker could, in principle, be persuaded to consider the possibility of demonic possession if the data were overwhelming. Nothing that Gallagher offers as evidence for demonic possession, however, approaches the realm of the extraordinary.

Implications for Mental Health Practice

Finally, it should be noted that many practicing mental health professionals occasionally encounter nonpsychotic individuals who express concerns about the possibility of demonic possession, alien abduction, sightings of long-deceased individuals, and other implausible phenomena. Indeed, large swaths of the population believe in these and related paranormal claims (Rice 2003). At the end of his piece, Gallagher asserts:

Those who dismiss these cases unwittingly prevent patients from receiving the help they desperately require, either by failing to recommend them for psychiatric treatment (which most clearly need) or by not informing their spiritual ministers that something beyond a mental or other illness seems to be the issue. For any person of science or faith, it should be impossible to turn one’s back on a tormented soul.

To the contrary, rigorous skepticism is not equivalent to denying a suffering individual care. Furthermore, as a psychiatrist, Gallagher is not obliged to confirm or disconfirm his client’s belief in demonic possession. Rather, his job is to improve his or her psychological adjustment. Some well-meaning mental health professionals, in an effort to enhance their clients’ functioning, “join the resistance” by engaging in discussions regarding the veracity of their claims, however fantastical they may be (Lebow 2006). At some point, however, responsible psychotherapists should begin to explore ways in which the client may hold such beliefs while still functioning adaptively. In other cases, therapists may need to encourage their clients to consider alternative explanations for their bewildering thoughts and experiences. By endorsing a set of paranormal beliefs, embracing what is more akin to an antiscientific mind-set, and going beyond joining with the client, Gallagher sets the stage for other practitioners to do more harm than good. At a bare minimum, clients deserve mental health practitioners who understand the nature of science and appreciate the value of critical thinking skills, demonic possession be damned.


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Scott O. Lilienfeld

Scott O. Lilienfeld, PhD, is a professor of psychology at Emory University. He is coeditor of the book Science and Pseudoscience in Clinical Psychology, Second Edition (2014) and author of several other books about science and pseudoscience in psychology.