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Robert Todd Carroll

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ganzfeld experiment, Ʈ

    κ ڵ ִ Ϸ Ѵ. ׷ ʽɸڵ Ϸ Ѵ. RTC

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̳ ðڱ,  پ ߿ õȴ. ۽ڴ ǥ ϴ , ڴ ڽ Ҵ Ͽ Ѵ. ۽ڰ ڰ Ͱ Ѵ. "Ʈ " Ǹ ڿ ΰ ְ ( ), ۽ŵ ˸ · Ʈ ¿ 󸶸ŭ ġϴ Ű Ѵ. ڰ ۽ ġϸ " " Ѵ. ڱ Ʈ ϸ ( ¥ ), ִ Ȯ 0.25 ȴ.''[Bem and Honorton]

Ʈ â ʽɸ ȣ , ʴɷ Ѵٸ, ۽ڿ ġ 쿬 ̶ ̾. ȣ 240 ڸ ̿Ͽ ùٸ ü 34̾ٴ ߴ. ̰ 쿬 ʴ´. ̰ ʴɷ¿ ϱ? ׷ ִ. , ٸ , ̳ , ̳ ð ڱ ̳, ð ̳ ׸ 谡 ִ. 쿬 ¾ ɼ ɼ Ұ ʴ. ¶ų, ȣ 뺧 ޱ ٸ ڰ ؼ, ̷ ִ ʴɷ»̶ ִ ̲ Ѵ.


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Rick E. Berger, Ph.D., the creator of the automated ganzfeld (and coauthor with Honorton on several ganzfeld papers) objects to the above conclusion, which he claims is "seriously outdated or you are unaware of the replications and published meta-analyses of this literature." Dr. Berger quotes the illustrious Dean Radin:

From 1974 to 1997, some 2,549 ganzfeld sessions were reported in at least forty publications by researchers around the world. After a 1985 meta-analysis established an estimate of the expected hit rate, a six-year replication was conducted that satisfied skeptics' calls for improved procedures. That "autoganzfeld" experiment showed the same successful results.

"The overall hit rate for the 2,549 sessions was 33.2% (where 25% was expected) yielding odds against chance of a million billion to one," says Berger. This sounds impressive until you examine the claim ever so slightly. The Ganzfeld is set up so that an interpretation must be made of a verbal report from the test subject to be matched against an image allegedly sent telepathically to the subject. Thus, even if an image bears little or no resemblance to the verbal description, if it is selected as the one most closely resembling the image verbally described, then it counts as a hit. For example, here is a verbal description taken from Dr. Berger's website on the ganzfeld: 

I see the Lincoln Memorial...
And Abraham Lincoln sitting there... It's
the 4th of July... All kinds of fireworks...
Now I'm at Valley Forge... There are
fireworks... And I think of bombs
bursting in the air... And Francis Scott
Key... And Charleston..
.

There are quite a few images that would "match" this description, since the description itself contains at least eight distinct images (the Lincoln memorial, Lincoln, 4th of July, fireworks, Valley Forge, bombs, Francis Scott Key, Charleston) to which one could easily add a couple more, such as the American flag, the star spangled banner, and, oh yes, George Washington, which was the image selected as most closely resembling the verbal description. We're not told what the other three choices were.

One wonders why, if this 8.2%, million billion to one, difference is evidence of telepathy, the verbal descriptions are not more precise. For example, whey didn't the psychic "see" George Washington, since that was what the image was? Why did he see the Lincoln memorial and a bunch of other things? How can they be sure of what they are measuring? Why isn't the subject allowed to choose "none"? Shouldn't the experimenters have some cases where the sender doesn't really send anything? And shouldn't the receiver be able to say "I'm not getting any message at all"? If Berger and Honorton would do a ganzfeld where the sender sends no messages at all throughout the entire experiment, my guess is that the receiver would still "receive" and give a verbal description of his vision. What would his vision be of? Would these scientists say that the vision is one of the imagination or would they say that someone, somewhere, sent some message and the subject picked it up? How can they be sure, in fact, that their subjects are not picking up messages from others besides the sender? Perhaps the reason the subjects fail 66.8% of the time is because they are picking up messages from the wrong senders. Maybe there is 100% telepathy. Or maybe something else is going on besides telepathy.

In any case, Julie Milton and Richard Wiseman recently published their own meta-analysis of ganzfeld studies and concluded that "the ganzfeld technique does not at present offer a replicable method for producing ESP in the laboratory" (1999).


б ڷ

Hyman, Ray. "Evaluation of Program on Anomalous Mental Phenomena," Journal of Scientific Exploration, Volume 10 Number 1.

Hyman, Ray. The Elusive Quarry: a Scientific Appraisal of Psychical Research (Buffalo, N.Y.: Prometheus Books, 1989).

Milton, J. and R.Wiseman (1999)  "Does psi exist? Lack of replication of an anomalous process of information transfer" PSYCHOLOGICAL BULLETIN, 125 (4), 387-391.

Schick Jr., Theodore and Lewis Vaughn. How to Think About Weird Things 2nd. ed.  (Mountain View, California: Mayfield Publishing Company, 1998).

Copyright 1998
Robert Todd Carroll

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