Psychic Powers

James "The Amazing" Randi has, through various demonstrations, cast doubt on Geller's claims of psychic powers. Geller has sued Randi. This case has now been completed, and Geller has lost. However Skeptics are still advised to exercise extreme caution in addressing this topic, given Geller's history of litigation.

One of Geller's more (in)famous claims is that he has made millions by finding oil. The following was posted by James Randi on this subject:

Geller SAYS that he has made fortunes with mining companies. When CSICOP checked this out, it was found that only one mining company, ZANEX, ever paid Geller, and that was far far less than the million dollars he says he got from 11 mining companies. Dont always believe everything that he claims, or didn't you learn that already?

Geller's stage appearances feature a range of stage magic. For more details on how he does his tricks, read books by James Randi, especially "The Truth About Uri Geller". Here are some hilights:

* "Broken" watches are often just gummed up. Warm it, shake it, and it will start ticking. Whether it carries on ticking or keeps good time is another matter.

* Spoon bending is usually done by misdirection. Get everyone to look away while you bend the spoon. Geller has even been known to hold up a bent spoon and say "its bending, its bending" while gradually revealing more of the bend between his fingers.

2.2: I have had a psychic experience.

That is pretty remarkable. But before you post to the Net, consider:-

• Could it just be coincidence? The human mind is good at remembering odd things but tends to forget ordinary things, such as premonitions that didn't happen. If psychic experiences happen to you on a regular basis then try writing down the premonitions when you have them and then comparing your record to later events.

• If you think you have a mental link with someone you know, try a few tests with playing cards.

• If you are receiving messages from elsewhere (e.g. UFOs), ask for specific information that you can then check. The complete prime factorisation of 2^1024+1 would be a good start: we don't know it, but any proposed answer is easy to check.

If you want to make a formal registration of your predictions, send mail to .

There is a book by Prof Robert Morris and Dr Richard Wiseman called Guidelines for Testing Psychic Claimants. University of Hertfordshire Press, 1995, pp 72, stlg7 pbk

2.3: What is "Sensory Leakage"?

Sensory leakage is something that designers of tests for psi must be careful to guard against. Tests for psi use powerful statistical tests to search for faint traces of communication. Unfortunately the fact that communication has taken place does not prove that it was done by telepathy. It could have been through some more mundane form of signal.

For instance one experiment involved a "sender" in one room with a stack of numbered cards (1-10) and a "receiver" in another room trying to guess what the next card was. The sender looked at a card and pressed a button to signal to the receiver. The receiver then tried to guess the number on the card. There was a definite correlation between the card numbers and the guesses. However the sender could signal the receiver by varying the delays between buzzes. When this channel of communication was removed, the effect disappeared.

2.4: Who are the main psi researchers?

Targ and Puthoff spring to mind, but actually, Puthoff is no longer doing psi research (I don't have any idea what Targ is up to these days.) Granted, their SRI work is quite famous, but if we want to review the historical (rather than currently active) figures, you probably want to go back at least as far as the Rhines.

Helmut Schmidt, a physicist who has been looking at PK, is still active at the Mind Science Foundation in Texas. (Sorry, I don't know a more specific address than that.)

The Foundation for Research into the Nature of Man (FRNM), which is what Rhine's work at Duke eventually developed into, is still active near Duke. It is currently headed by K. Ramakrishna Rao.

The Koestler Chair of Parapsychology at the University of Edinburgh is still active. The current incumbent is named Robert Morris; his main assistant is Deborah Delanoy. He and Dr Richard Wiseman have written a small book "Guidelines for Testing Psychic Claimants". [Does anyone have publisher details?]

Roger Nelson is active in the Princeton Engineering Anomalies Research center (PEAR) and occasionally posts to the net.

Active workers in the field that I can think of currently include Dean Radin, who also posts to sci.skeptic as <dir2@gte.com>, Jessica Utts, and Ed May. The Parapsychological Association has a much larger roster than that, of course, but I'm not a member myself and don't have access to their membership roll.

2.5: Does dowsing work?

Dowsing is the art of finding underground water by extra-sensory perception. Sometimes tools are used. The traditional one is a forked hazel stick. When held in the correct way this will twitch in response to small muscle movements in the back and shoulders. Another tool that has become popular in recent years is a pair of rods mounted in tubes that are held in each hand just in front of the user.

        Rod bent into tube.
        |
        V
       	r-------------------------------
       ||                    ^
       ||                    |
       || <- Tube           Rod
       ||
       ||
       ||

When water (or something else) is dowsed, the rods turn towards each other. Like the forked hazel stick it amplifies small movements of the arm and shoulder muscles.

Unfortunately careful tests of dowsers have revealed absolutely no ability to find water or anything else by extra-sensory perception. Dowsing success stories can be explained by noting that wherever you dig you will find water. You just have to dig deep enough. It has also been suggested that dowsers may unconsciously use clues in the environment.

James Randi has tested more than 100 dowsers (I don't know the actual count). He tells that only 2 tried to cheat. This suggests that dowsers are basically honest people.

The Skeptical Inquirer has published a number of articles on dowsing. James Randi's "A Controlled Test of Dowsing" was in vol. 4, no. 1, pp. 16-20. Michael Martin's "A New Controlled Dowsing Experiment" was in vol. 8, pp. 138-140. Dick Smith's "Two Tests of Divining in Australia" was in vol. 6, no. 4, pp. 34-37. Randi's book Flim-Flam! has a section on dowsing. The main skeptical book about dowsing is Vogt, E.Z. and Hyman R. (1959, 2nd edition 1979) Water Witching USA. The University of Chicago Press. 260 pages. Available as a paperback.

2.6: Could psi be inhibited by the presence of skeptics?

Psychic researchers have noted something they call the "shyness effect" (or more grandly "psi-mediated experimenter effects"). This is invoked to explain the way in which many subjects' psychic powers seem to fade when exposed to careful scrutiny and proper controls. Often it is alleged that having a skeptic in the audience can prevent the delicate operation of psi.

In its most extreme form this hypothesis becomes a "catch-22" that makes any results consistent with a psi hypothesis. This renders the hypothesis unfalsifiable and therefore unscientific. Less extreme forms might be testable.

2.7: Why don't the skeptics test the real psychics?

A claim is sometimes made that the Skeptics movement only tests those psychics which it knows to be frauds. The real psychics are supposedly being ignored by skeptics who are afraid to be proved wrong.

There are three problems with this claim.

Firstly, it assumes that all the skeptics are engaged in a conspiracy to persuade the world that psychic powers do not exist. This is only a Petty Conspiracy theory (see section 0), since it only requires the involvement of a few dozen of the most prominent skeptics, but it is still difficult to see any motive for such a deception. "Fear of being proved wrong" implies that they already know they are wrong, which makes their continued activity rather puzzling.

Secondly, most skeptics are always ready to take part in any reasonable test. The "real" psychics are perfectly at liberty to challenge the skeptics.

Thirdly, there are always more alleged psychics. Hence this argument presents the skeptics with an ever-receding target. The dialogue goes something like this:

Paranormalist: Yes, I concede that Mr. Adams is a fake, but what about
	       Mr. Brown.  The things that he does could never be
	       faked.

[Some months later]

Skeptic: Here is how Brown did it....

P: OK, I concede that Adams and Brown are fakes, but Mrs Carver is the
   surely the real thing.

[Some months later]

S: Here is how Carver did it...

P: OK, maybe Adams, Brown and Carver were fakes, but what about Digby
   and Ender?

S: I give up.  There's no convincing some people.

P: [shouting] Digby and Ender are real psychics: the skeptics are
   afraid to test them.  They only test the fakes!

2.8: What is the ganzfeld?

A state of sensory deprivation which may enhance psychic abilities. The subject lies on a soft bed, with a "white noise" hissing sound played through headphones and half of a ping-pong ball placed over each eye to give an empty field of view. The subject then talks to a tape recorder, describing any ideas which enter his or her mind.

To test whether psychic communication is occurring, a "sender" concentrates on some image while the "receiver" is in the ganzfeld. Then the image is shown to the receiver along with three other images. The receiver must pick the image that was seen by the sender.

Dean Radin <dradin@festival.ed.ac.uk> has been conducting some careful ganzfeld experiments, which he describes as follows:

... our unit has recently conducted pilot replications of the ganzfeld telepathy studies reported by Bem & Honorton. In 76 sessions we obtained 25 direct hits, which is quite close to the 33% meta-analytic hit rate previously reported by Honorton et al..

Our methodology was based on Honorton's auto-ganzfeld setup, which automated most aspects of the experiment, except we were even more obsessive: Our system uses a computer to randomly select the target, to automatically present the target clip to the sender, to automatically present the judging clips in a random order to the receiver, and to store the data. The receiver and sender rooms are 25 meters apart, behind 4 doors, and sound-shielded to 100 dB.

We only use volunteer subjects claiming no special abilities, typically for one or two sessions. The methodology and preliminary study results will be reported in detail in August at the annual Parapsychological Association convention. Some of our other plans are reported in the 15 May 93 New Scientist cover article on telepathy.