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Charles Honorton, in his classic article Rhetoric Over Substance noted an important difference between the psi controversy and more conventional scientific disputes. Controversies in science normally occur between groups of researchers who formulate hypotheses, design experiments, and then collect data in order to test their hypotheses. But as Honorton wrote, “In contrast, the psi controversy is largely characterized by disputes between a group of researchers, the parapsychologists, and a group of critics who do not do experimental research to test psi claims or the viability of their counterhypotheses.”
But as Honorton pointed out, “Gardner does not attempt to document this assertion, nor could he. It is pure fiction. Look for the skeptics’ experiments and see what you find.” For the most part, skeptics have simply criticized from the sidelines, and have produced no experimental research of their own. One notable exception to this rule has been British psychologist Susan Blackmore. She began working on a PhD in parapsychology in the 1970’s, but has repeatedly claimed that she has failed to find any evidence for the existence of psi. For instance, she wrote in 1996: “When I decided to become a parapsychologist I had no idea it would mean 20 years of failing to find the paranormal.” Blackmore has made a career for herself as one of the world’s most well known skeptics of psi, and in 1988 was elected a Fellow of CSICOP. In a number of publications Blackmore claims to have become increasingly skeptical of the existence of psi phenomena after “ten years of intensive research in parapsychology.” These claims led parapsychologist Rick Berger to critically examine the Blackmore experiments in great detail, and he found that “The claim of ‘ten years of psi research’ actually represents a series of hastily constructed, executed, and reported studies that were primarily conducted during a 2-year period.’” These consisted of a set of experiments conducted between October 1976 and December 1978 for her PhD dissertation. Blackmore reported 29 experiments completed over this two-year period, of which 21 were eventually published as separate experiments in five parapsychology journal papers. Seven of these experiments produced statistically significant results. Although these experiments form the basis of Blackmore’s claim of “failing to find the paranormal”, the odds against 7 successes out of 21 happening by chance are over 20,000 to one! So, how does Blackmore reconcile the fact of 7 successful experiments out of 21 with her often-repeated claim that her own research led her to become a skeptic? Simple: results from successful experiments were dismissed as due to flaws in the experiment, yet study quality was simply ignored when the results were nonsignificant. There are many design flaws that can lead to false positive results, but there are also many that can lead to false negatives, such as inadequate sample size (low statistical power), inappropriate sampling, and so forth. Berger writes “Blackmore’s database is replete with examples of such flaws”, and continues:
In other words, our decision to invoke study flaws to dismiss the results of an experiment should not be influenced by our preconceptions of what the result “should have been.” But this seems to have been exactly what Blackmore has done in order to justify her beliefs, as evidenced in the following remark of hers:
As we shall see, this appeal to ‘science’ as a monolithic body of conclusions that tell you in advance what should and should not be the case is a rhetorical tactic often used by Blackmore. But at any rate, Berger finally concluded:
The same journal issue also includes a response by Blackmore to Berger’s critique, in which Blackmore conceded “I agree that one cannot draw conclusions about the reality of psi based on these experiments.” Near the end of his critique Berger had written “During my aborted meta-analysis of Blackmore’s published work, I was struck by patterns in the data suggestive of the operation of psi…. Without a serious meta-analysis of the original unpublished source material, complete with weighting for flaws…the issue of whether the Blackmore experiments show evidence for psi cannot be resolved.” Presumably eager to nip this embarrassment in the bud, Blackmore hastened to say “I am glad to be able to agree with his final conclusion - ‘that drawing any conclusion, positive or negative, about the reality of psi that are based on the Blackmore psi experiments must be considered unwarranted.’” It is interesting to examine Blackmore’s writings before and after Berger’s critique. Two years earlier, in an article for the Skeptical Inquirer entitled “The Elusive Open Mind: Ten Years of Negative Research in Parapsychology” she wrote:
In another article written at about the same time she wrote:
Although after Berger’s critique Blackmore was willing to concede in an academic journal that “I agree that one cannot draw conclusions about the reality of psi based on these experiments”, her writings in the popular press have not reflected this admission. Commenting on the ganzfeld experiments in a newspaper article in 1996, she wrote:
Wouldn’t a more honest reaction be for Blackmore to admit in the popular press that “one cannot draw conclusions about the reality of psi” based on her own experiments, and that a scientific opinion should be based only upon a critical evaluation of other peoples’ published works? But perhaps this is asking too much. After all, Blackmore pursued a PhD in parapsychology in order to become a “famous parapsychologist”. Having failed to produce research supporting the psi hypothesis, she evidently decided to try to make a name for herself by attacking the psi hypothesis, which must at the time have seemed to be an easy target. Apparently, though, in a recent article she claims to have given up. “At last, I’ve done it. I’ve thrown in the towel”, she wrote.
We’ll miss you, Susan Susan Blackmore Skeptic or Dogmatist? |
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