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The Wisdom of Psychopaths
In this engrossing journey into the lives of psychopaths and their infamously crafty behaviors, the renowned psychologist Kevin Dutton reveals that there is a...
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Psi, or the paranormal, denotes anomalous psychological effects that are currently unexplained by normal causes. Historically such phenomena eventually are either accounted for by normal means, or else they disappear under controlled conditions. But now renowned psychologist Daryl J. Bem claims experimental proof of precognition (conscious cognitive awareness) and premonition (affective apprehension) “of a future event that could not otherwise be anticipated through any known inferential process,” as he wrote recently in “Feeling the Future” in the Journal of Personality and Social Psychology.
Bem sat subjects in front of a computer screen that displayed two curtains, behind one of which would appear a photograph that was neutral, negative or erotic. Through 36 trials the subjects were to preselect which screen they thought the image would appear behind, after which the computer randomly chose the window to project the image onto. When the images were neutral, the subjects did no better than 50–50. But when the images were erotic, the subjects preselected the correct screen 53.1 percent of the time, which Bem reports as statistically significant.
Bem calls this “retroactive influence”—erotic images ripple back from the future—or as comedian Stephen Colbert called it when he featured Bem on his show The Colbert Report, “extrasensory pornception.”
For many reasons, I am skeptical. First, over the past century dozens of such studies proclaiming statistically significant results have turned out to be methodologically flawed, subject to experimenter bias and nonreproducible. This assessment by University of Amsterdam psychologist Eric-Jan Wagenmakers appeared along with Bem’s study in the same journal.
Second, Bem’s study is an example of negative evidence: if science cannot determine the causes of X through normal means, then X must be the result of paranormal causes. Ray Hyman, an emeritus professor of psychology at the University of Oregon and an expert on assessing paranormal research, calls this issue the “patchwork quilt problem” in which “anything can count as psi, but nothing can count against it.” In essence, “if you can show that there is a significant effect and you can’t find any normal means to explain it, then you can claim psi.”
Third, paranormal effects, which are rarely allegedly detected at all, are always so subtle and fleeting as to be useless for anything practical, such as locating missing persons, gambling, investing, and so on. Fourth, a small but consistent effect might be significant (for example, in gambling or investing), but according to Hyman, Bem’s 3 percent above-chance effect in experiment 1 was not consistent across his nine experiments, which measured different effects under varying conditions.
Fifth, experimental inconsistencies plague such research. Hyman notes that in Bem’s first experiment, the first 40 subjects were exposed to equal numbers of erotic, neutral and negative pictures. Then he changed the experiment midstream and, for the remaining subjects, just compared erotic images with an unspecified mix of all types of pictures. Plus, Bem’s fifth experiment was conducted before his first, which raises the possibility that there might be a post hoc bias either in running the experiments or in reporting the results. Moreover, Bem notes that “most of the pictures” were selected from the International Affective Picture System, but he does not tell us which ones were not, why or why not, or what procedure he employed to classify images as erotic, neutral or negative. Hyman’s list of flaws numbers in the dozens. “I’ve been a peer reviewer for more than 50 years,” Hyman told me, “and I can’t think of another reviewer who would have let this paper through peer review. They were irresponsible.”
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4 Comments
Add CommentProbably nobody will be able to prove such things, but there are some approaches thru physics to this: mind reading may be a combination of high sensibility to face and body changes of scrutinized person, and also the brain produces electric currents and fields; for premonitions, there are the relativity theory of space and time, and for influence on others, the use of imperceptible body sings, and why not, quantum entanglement. This kind of game is better done with mentalists; starting from Mesmer, it seems that there are always some of them
Reply | Report Abuse | Link to thisThis critique is probably a mix of fair and unfair criticisms. One-tailed t-tests are seldom used, but for no particularly principled reason. Much like the typical significance criterion (.05) in NHST, this is just convention. Both type-1 and type-2 errors can be dangerous depending on the situation. There is nothing innately wrong with a one-tailed test. Similarly, a vanishingly small effect can be either important or unimportant depending on the larger theoretical context of the experiment. Explaining the last 1% of unaccounted variance in a highly determined, well characterized domain can be valuable. Last, it is very common in psychology experiments to supplement a normed set of images or words in order to increase one's experimental power. In so far as Bem has provided the images for replication, I don't think this poses a significant methodological flaw. However, at the root of the problem of this and other psi/prayer/esp/paranormal research is the patchwork problem. Type-1 errors will always occur. They will be frequent in active research areas. This is why replication is essential. I'm confident that this effect will not replicate, because so many other experiments have failed to produce positive evidence of psi phenomena. While we can consider these unlikely possibilities, we should probably maintain a strong prior against them.
Reply | Report Abuse | Link to thisThe quote that Mr Shermer attributes to Daryl Bem is cherry-picked, as anyone who reads it in context will recognise.
Reply | Report Abuse | Link to thisI have known Daryl Bem for a very long time, having been fortunate to be the beneficiary of his guidance on my dissertation committee at Cornell in 1975-1979.
Reply | Report Abuse | Link to thisThere are certainly many issues open to legitimate debate and even skepticism regarding his psi experiments, and to the responses of his critics, including Shermer of Scientific American.
There is one point I have not seen in any of the responses to Bem's work. Perhaps the greatest pleasure in working with him was his almost obsessive insistence on provoking debate, sometimes holding his own beliefs close to his chest. He was consistently more dedicated to that goal than to pontificating on what he believed to be The Truth.
Despite Bem's spirited defense of his precognition studies, I would not swear in a court of law that he truly, down-deep, believes in precognition. I don't think that spreading wisdom or scientific discoveries are his top priorities. Rather, in the finest tradition of great science, he is a man who believes that few professional pursuits are nobler than to provoke honest and rigorous debate among careful, well-trained investigators.
Of course his career has been an enormous gift to social psychology. But if he is remembered only for his success at provoking high-quality debate, then he will be remembered as a hero, at least by me.
David L. Ransen, Ph.D.
http://delrayholistictherapy.com
DrRansen@DelrayHolisticTherapy.com