The report which we publish below is based
on the 1979 report deposited in typescript in the Society’s
library where it was available to interested persons on request. The
author has now decided that it would be fairer to all concerned if
this report were now brought into the public domain. Accordingly we
are now publishing it in a slightly emended form and have invited
those who consider themselves to be explicitly criticized therein to
write a rejoinder—Editor.
In 1979 I visited the laboratory of Dr. Carl
Sargent at the University of Cambridge to observe highly successful
ganzfeld psi experiments then in progress. I observed 13 sessions,
of which six were direct hits. I considered whether the results
might be accounted for by sensory leakage, experimental error,
cheating or psi. I made observations of the sessions to test these
hypotheses. The experimental design effectively ruled out sensory
leakage. However, I observed several errors in the way the protocol
was observed. Most of these occurred in the cumbersome randomisation
procedure. It was not clear how these errors came about. Their
origin might have been clarified by either (a) a statement from
Sargent or his colleagues, or (b) by reanalyses of the raw data.
However neither has been made available. Sargent's nine ganzfeld
studies form a considerable proportion of the total ganzfeld
database. In view of Sargent's unwillingness to explain the errors
found, or to make his data available to other researchers, I suggest
that these results should be viewed with caution.
In November 1979 I went to visit Carl Sargent's
laboratory at the University of Cambridge. He had carried out
numerous ganzfeld experiments with highly successful results
(Sargent 1980). Meanwhile I had been unsuccessful in
superficially similar ganzfeld experiments at the University of
Surrey (Blackmore 1980).
The objective of the visit was to observe the
methods and conditions used at Cambridge and compare them with those
used at Surrey, to see whether any reason for the discrepancy in the
results could be determined. Because of the possibility of a
psi-mediated experimenter effect, Sargent and I hoped to carry out
experiments in which we would both act as experimenter while using
the same subjects and procedure. Sargent kindly invited me to visit
his laboratory for a month. The Society for Psychical Research (SPR)
provided a grant to cover my expenses while there. In the event I
was only able to stay eight days from November 22-30 1979.
During the visit I observed several errors in
the way that the protocol was observed and the randomisation
procedure carried out. The source of these errors was unknown. After
the visit I wrote a report for the SPR (a condition of the grant)
which was placed in the Society's office and was available to any
member who wished to see it.
The account which follows is based on four
sources of information. 1. My original report for the SPR (which is
still available from them). 2. My notes which I made during the
visit to Cambridge. 3. My private diaries written each day. 4.
Letters between myself, Sargent and other interested parties.
THE EXPERIMENTAL PROCEDURE
At the time of my visit three ganzfeld
experiments were in progress. I observed a total of 13 sessions. I
either watched the experimenter and subject, or the agent, or acted
as one of these myself. The experimenters were Sargent, Trevor
Harley and student experimenters (G. M., J. L. and K. R.). The
subjects and agents were all of these, plus other students and
friends of the experimenters.
All experiments used the same procedure,
outlined below, with the following variations. In one experiment
subjects could remain in ganzfeld for as long as they wished. In
another, sessions lasted either 15 or 30 minutes, and the third
involved a study of subject-agent pairs. There was also one session
conducted at a private house for the benefit of the BBC and for this
the procedure was, necessarily, slightly different. With these
variations, the procedure was as follows.
The subject arrived at the experimental room
where Sargent or the student experimenter gave them coffee, chatted
with them and, if the subject was a novice, explained the purpose of
the experiment and the procedure. There was often music playing and
the atmosphere was very informal and relaxed. In some cases the
subject brought a friend to be agent, but in most cases an
experimenter acted as agent.
When the subject was ready the experimenter
gave him or her a pre-session questionnaire to complete. The subject
then lay on a comfortable mattress on the floor and was prepared for
the ganzfeld. Half ping-pong balls were fixed over the eyes with
sellotape and cotton wool and white noise was played through
headphones, adjusted to be comfortably loud. A red light was shone
on the ping-pong balls. The subject was then left alone and the door
shut. The experimenter's and agent's watches were synchronised from
the start of the ganzfeld session.
The experimenter then retired to the control
room from which he could watch the subject throughout the session
through a one-way mirror. A microphone near the subject's head
picked up everything that was said. This was relayed to the control
room and was both recorded on tape and written down by the
Meanwhile the agent alone (if one of the
experimenters was to be agent) or the agent with an agent's
experimenter, went along the corridor into Sargent's office to
select the target for that session. There were 27 sets of pictures,
each containing four black and white or coloured pictures, chosen by
Sargent and Harley to be as different as possible from each other.
One of these was selected by using random number tables. There were
two copies of each set. One contained the four pictures in
individual sealed large envelopes, for the agent. The other,
duplicate set, had all four pictures in one envelope and this was
left in the office.
In each set the pictures were lettered A to D.
Next a small sealed envelope containing a
letter A-D was selected and used to determine which of the four
pictures in that set was to be target. The randomisation
procedure is outlined in more detail below.
The agent took the four large envelopes and the
small envelope (all still sealed) to a different building and into a
soundproof booth. At a pre-arranged time (depending on the
experiment) the small envelope was opened. This contained a letter
A-D. The corresponding large envelope was then opened and the agent
took out the picture and looked at it for the prescribed length of
time making notes on a sheet provided. He or she retained the small
envelope with its letter.
The other three large envelopes remained
sealed. Afterwards he or she waited near a telephone in another room
on that floor of the building.
At the end of the ganzfeld session the
experimenter went into the subject's room, turned off the white
noise, removed the headphones and ping-pong balls and gave the
subject a post-session questionnaire to complete. He then went into
the office and collected the duplicate set of pictures, left there
by the agent He laid them out in order in front of the subject and
then went through the transcript of everything the subject had said.
Each picture was marked by the experimenter and subject
together, on a scale of 0 to 2 for correspondence with each item of
The various experimenters differed somewhat in
their approach to the judging and in the extent to which they
encouraged or guided the subject, but in all cases the total score
for each picture was added up and the subject then asked to rank and
rate (on a scale of 1-100) all four pictures.
Once the ranks and ratings were recorded the
experimenter telephoned the agent and asked him to come over. He
always used the same words when ringing. When the agent (and agent's
experimenter when applicable) arrived they disclosed which picture
was target and showed this, together with the other unopened
envelopes, and the letter A-D, to the experimenter and subject. The
rank allocated to the target was then known and a z-score based on
the ratings was calculated.
The randomisation procedure is briefly
described in Ashton, Dear Harley & Sargent 1981 and Sargent 1980. It
was rather complex and I shall therefore describe it in more detail.
There were 27 sets of four pictures, numbered
1-12 and 14-28. First the agent selected one of these by taking an
arbitrary starting point into the RAND random number tables, and
taking the first number between 01 and 28 (excluding 13). This
determined which set was to be used.
The pictures in each set were lettered A-D.
Which was to be target was determined as follows. There was a pile
of 20 small brown sealed envelopes constantly on the desk in the
office. Each contained two pieces of white card enclosing a slip of
paper bearing one of the letters A, B, C or D. There were five of
each letter in the pile, the envelopes being all of the same type
and unmarked. The agent (or agent's experimenter) opened the book of
random digits arbitrarily selected an entry point and took the first
number between 01 and 20. He counted this number of envelopes down
the pile and cut it. He then took the next number in the list, and
counted down the pile again, taking the envelope indicated. Once in
the soundproof room he opened his envelope and used the letter it
contained to determine which of the large envelopes would be
Afterwards the pile obviously contained only 19
envelopes. To restore it to 20 the one used had to be replaced; and
by one of the same letter. In four drawers adjacent to the desk,
spare envelopes were kept: A's in the top drawer, down to D's in the
bottom drawer. Like those in the original pile they were, of course,
of the same type and unmarked. Their contents were only known by
which drawer they came from. After each session the experimenter
looked up which letter had been used for that session, took an
envelope from the corresponding drawer and placed it in the main
pile. In this way the main pile could retain its contents unchanged.
During my visit I observed 13 sessions. Of the
12 conducted at the laboratory, six were direct hits. This is a hit
rate of 50 per cent when 25 per cent is expected by chance.
Obviously the number of sessions was small but the results seemed to
confirm Sargent's previous high rate of scoring.
OBSERVATIONS PHASE 1. DAYS 1-3
During the first three days of my visit I
observed five sessions (not counting the BBC session). During these
sessions I did not take part but just watched either the
experimenter or the agent. I took detailed notes, intending to
compare the procedure with my own. Of the five sessions, three
produced a rank 1 or direct hit, one a rank 2 and one a rank 4. That
is a hit rate of 60 per cent when 25 per cent is expected by chance
(p = -12). These results seemed quite unlike my own chance results.
The whole purpose of the visit was to try to
determine the reason for the difference in results between my
experiments and those of Sargent. I considered the following five
hypotheses and made observations accordingly.
1. Differences in 'atmosphere'
Sargent's setting and procedure appeared
to be potentially far more psi-conducive than mine. The room was
much larger and more pleasant. There was music and coffee and the
whole environment was much less like that of a laboratory.
2. Differences in experimenter
It was quite clear that the main experimenter
was extremely confident about the expected results and conveyed this
confidence to the subjects The experimenter's role during the
judging was also much more active with the experimenters, especially
Sargent, often encouraging the subject making suggestions and
pointing out correspondences. This would allow for more influence by
the experimenter, which might be good or bad. With a skilled
experimenter, it might maximise the use of the available
3. Sensory Leakage
The design seemed to exclude very efficiently
the possibility of sensory leakage. Duplicate target sets were used
so that no handling cues were available the subject and subject's
experimenter were entirely isolated from the agent from the time the
watches were set until the phone call was made By this time the
subject had made his choice. In the sessions I observed I could see
no means of sensory leakage unless protocol were violated. I
observed no such violations of protocol at this stage.
Three questions arise here. First does the
procedure allow for errors to take place? Second are those errors
likely to be important to the results, and third did any errors
The sort of accidental errors which might occur
include incorrect replacement of pictures in envelopes, errors in
the timing, in giving the right questionnaires in the addition of
marks or the calculation of z-scores.
First, the complex randomization procedure
seemed to allow for errors to take place reasonably easily. For
example, if an envelope were incorrectly replaced in the pile this
would lead to a bias in the pile which might never be detected.
Second, however, such a bias would produce only a small effect on
the overall scores.
Third, only one error was observed during this
stage. On one occasion, when the duplicate set of pictures was
brought in for judging, it was found to contain only three pictures
instead of four. The problem was efficiently resolved. J L (a
student) rang the agent (G. M.) (in my presence) and asked him to
see whether he had an extra picture by mistake and if so, to place
it on the ground floor of the other building and then return to his
place by the phone. Sargent then went to fetch it and the judging
proceeded as usual. This sort of error can easily arise in
experiments of this complexity but, if handled correctly like this,
could not produce spurious results. No other errors were observed at
I had no reason to suppose that anyone might be
cheating. However, parapsychology is still a controversial subject
and it is conventional to consider whether a protocol is proof
against obvious methods of cheating, even though completely
cheat-proof designs are not to be expected and are probably
unattainable. My intention was to look for any obvious methods and
to ensure that they were not taking place. In this way I could be
reasonably certain that the only remaining hypothesis was that of
Before the visit I had thought of several
possible methods. These involved the experimenter finding out which
picture was target, and pushing the subject towards it, or the agent
opening a different picture from the one specified by the
randomization. I could now see that the experimental design made any
of these methods extremely difficult. However, the complex
randomization procedure seemed to allow for several methods of
cheating. The observations necessary to check up on these were
simple and unobtrusive and I believed them to be necessary if I was
to convince myself and others of the validity of the results. This
led to the second phase of the observations during which I checked
various new hypotheses.
OBSERVATIONS. PHASE 2. DAYS 4—5
During these two days I observed a further five
sessions. I was subject in one of them. There were three direct
hits, one rank 2 and one rank 3. This is a hit rate of 60 per cent,
where 25 per cent is expected by chance. For these few sessions
alone, the results are almost significant (p = -055). For the ten
sessions observed so far the sum of ranks was 17 (p = -016).
Clearly chance was very unlikely to account for
these results. Sensory leakage or simple experimental error had been
excluded and so the remaining possibilities seemed to be either ESP
or cheating. I should point out that it was probably clear to
everyone in the lab that I was sceptical about the possibility of
ESP. I believe that having a sceptical observer there was not
particularly pleasant, but on the other hand the sessions proceeded
in a relaxed and pleasant atmosphere and the results were not
adversely affected by my presence. I did not tell anyone about the
specific hypotheses I had in mind. I hoped only to make some simple
observations which would exclude them to my own satisfaction.
With this in mind I considered whether
any simple methods of cheating were possible within this
experimental design. I considered the following hypothetical methods
and ways of detecting them.
1. The pile of small envelopes could be
biased. The experimenter would then know which picture would be
target and could 'push' the subject towards that one. This would
result in an overall bias in the targets used, unless the pile
were regularly replaced. This would mean having extra piles of
envelopes hidden somewhere.
2. The agent could guess which picture
the subject would choose. This would be especially easy if he knew
the subject well, or the subject had taken part in previous trials.
He could then cause this picture to be selected by several methods
a. By marking the main pile of
twenty envelopes and selecting the right one.
taking an envelope from a drawer instead of from the main pile.
c. By concealing extra envelopes to use for the purpose (I
thought of this some days later).
These methods would all be detectable. If (b)
occurred a small envelope would disappear from the drawer during the
trial instead of afterwards (during replacement). The pile might
also remain at 20, instead of 19, during the trial. Or if it were
reduced to 19, two envelopes would be used during one trial instead
of one. Also the pile would become biased because the one removed
would not match the one later replaced.
3. A most effective method would be for one
person to arrange both to carry out a false randomization (as in 2)
and also be present at the judging to 'help' the subject.
All these methods involve violations of
protocol. Some would be easily detectable and I therefore decided to
make certain simple observations which in no way interfered with the
running of the experiment or with anyone's privacy. If I found no
indications that any of them were happening, then I could be
reasonably confident that the results were due to ESP.
The effects predicted were as follows:
A. The main pile might be marked.
B. The main pile might be replaced-or partly
C. The main pile might be biased (this could
arise from several methods). The only way to check this would be to
open the envelopes which I did not wish to do (but see later).
D. There might be piles of extra envelopes
around the room. I thought it improper to search for them and did
not wish to do so.
E. Envelopes might disappear from the
replacement drawers during, rather than after, a session.
F. Two envelopes, instead of only one, might
disappear from the drawers for one session.
To check on these last two possibilities I
decided to count the numbers of envelopes in each drawer both during
each session and afterwards, and to watch the replacement procedure
To recap—my hypothesis was that if cheating
were taking place I would expect envelopes to disappear from the
drawers during, rather than after, a session, or for more than one
envelope to be used for each session.
The main pile did not seem to be marked and was not
switched during these two days. I counted the envelopes in the
drawers from session 8 onwards. The results are shown in Table 2.
From this table it can be seen that between
sessions 8 and 9 two envelopes, not one, disappeared from the
drawers. One was a 'D' (which is correct to replace the 'D' which
was target for session 8). The other was a 'B'. This was target for
session 9, but of course the 'B' for that session should have come
from the main pile; only being replaced later by one from the
I later observed the replacement procedure and
this was carried out correctly. i.e. another 'B' was taken from the
drawer and placed in the main pile.
If the 'B' for trial 9 had come from the
drawers instead of from the main pile (as hypothesised in 2b above)
this would probably result in there being an extra 'B', instead of
some other letter, in the main pile. I was unable to check on this
at this time.
I noted certain other problems all concerning
the same trial. During this trial (No. 9) I stayed with the
experimenter (K. R.) and watched the judging. Sargent was not
officially taking part, but he came in during the judging. He said
he wanted to help, because it was a particularly difficult session,
the subject having said only a few words. He seemed to push the
subject towards picture B. I wrote this observation in my notes at
the time and K. R. independently mentioned it tome as well. Note
that I wrote down this observation before I counted the envelopes in
the drawer. Of course this ought not to matter because Sargent
should not have had any way of knowing the identity of the target
(but see later).
On the same trial there was also an
arithmetical error: it was later discovered that the experimenter
had added up the marks wrongly. Picture B had not been given the
most marks and so this session should not have been a direct hit.
When he discovered this Sargent checked the addition for all
previous trials and found nothing else wrong. Rejudging would be one
way to clarify whether there really was a good correspondence
between the subject's mentation and the picture B. Sargent said that
he intended to do this rejudging.
OBSERVATIONS PHASE 3 DAYS 6-7
I intended to continue observing. I also
considered asking Sargent whether we could open the envelopes in the
main pile to see whether it had become biased as hypothesised.
However, Sargent became ill with 'flu' and was away on Day 6. I was
therefore unable to observe any more sessions or to ask him about
the main pile.
In Sargent's absence I discussed the
experimental design and its potential problems with Trevor Harley. I
told him that I was worried that the main pile of 20 envelopes might
become biased, and no-one would know it had happened.
He assured me that Sargent always did the
replacement himself and that he would not make such errors.
Nevertheless, he thought it was a good idea to open them to find
out. He checked that there were new envelopes of the same kind
available. I then opened all the envelopes. There were 19, the
replacement for the previous trial not yet having been done. There
should have been 4 'A's, 5 'B's, 5 'C's and 5 'D's. There were in
fact 5 'A's, 6 'B's, 4 'C's and 4 'D's. As I had predicted there was
an excess of 'B's.
Harley and I discussed the possible ways this
error could have come about. These include:
1. Accidental errors made originally in
2. Accidental errors made in replacement to the
main pile. Two such errors could create the bias observed.
3. As a by-product of the methods (of cheating)
We then opened the envelopes in the drawers.
Drawers B-D were correct but the 'A' drawer contained 2 'D's in
addition to several 'A's. Harley and I replaced all the letters in
new envelopes and reconstituted the main pile correctly.
Because of finding these errors I discussed
with Harley the reasons I had for worrying about them. I explained
about the missing 'B' on session 9, and the other observations made
concerning that session. Harley immediately recalled that on that
session there had been a change from the official procedure.
Harley was to be agent. It was an experiment in
which there was little time for the agent to do the randomization.
Harley therefore asked Sargent to prepare things for him; apparently
meaning him to get all the envelopes, tables and so on ready. In
fact Sargent actually carried out the randomization and handed
Harley the set of pictures and the small envelope. Harley took them
and used them for that session. This should not have mattered since
officially Sargent was to have no further role in that session.
However, of course, we now knew that Sargent had come into the
judging session on that occasion and had apparently 'pushed' the
subject towards the correct picture.
The following day Sargent was still away ill.
Harley and I wished to check up on some details of previous sessions
and therefore looked for the book in which they were recorded. We
could not find it, but in the process Harley found a sealed
envelope, like those used in the randomization, under some papers.
We decided to look for any further ones. We found a single one in a
drawer and a pile of three under some papers. We opened them all.
The single ones were a 'C' and a 'D'. The pile of three were all
'A's. We found no 'B's.
We discussed possible reasons for them being
there. One possibility appeared to be the method 2c, outlined above.
If there were no 'B's concealed, then only method 2b could be used
and would result in a 'B' going missing from the drawers, as
observed on trial 9. We discussed alternative explanations.
Harley said that the envelopes for this series
of experiments had been specially prepared all at once and placed
either in the main pile or the drawers. Envelopes of that size and
colour had not been used in any previous experiment. He could think
of no reasons for there being any extra ones around the room.
Two further sessions were conducted, by student
experimenters, in Sargent's absence. These obtained ranks 3 and 4;
When Sargent returned after his illness Harley
presented him with the findings so far. These were:
1. The bias in the main pile and errors
in the drawers.
2. The extra envelopes found around the
3. The series of events surrounding session 9.
Sargent denied that any of these errors had
come about deliberately and supplied alternative explanations for
them. I hoped that Sargent would write his own account and provide
these explanations himself. Since he has never done so I shall try
to be fair to what he told me. We now have two alternative
hypotheses to account for the findings.
1. I had predicted that certain methods of
cheating would lead to a bias in the main pile. I found that bias.
Sargent said that the errors in the pile must
have come about by accidental errors in replacement.
He calculated the maximum size of any spurious
effect that could be created by this bias and found it to be only 3
per cent; a negligible effect when the average hit rate was about 45
per cent. Clearly if the bias were accidental it could not account
for the successful results. On the other hand if it came about as a
by-product of those methods of cheating, a very large effect size
could be obtained.
At this time the error in addition (mentioned
above) was also found. Neither Sargent nor I had any explanation for
the 'D's in the 'A' drawer.
2. I had predicted that certain methods of
cheating would necessitate having extra piles of envelopes hidden
around the room. These were found.
Sargent explained that the extra envelopes had
been left over from a previous experiment, although Harley had
previously said that this was very unlikely.
3. It now appeared that on one session—number
9—the following events had taken place.
1. Sargent did the randomization when he
should not have.
2. A 'B' went missing from the drawer during
the session, instead of afterwards.
3. Sargent came into the judging and 'pushed'
the subject towards 'B'.
4. An error of addition was made in favour of
'B' and 'B' was chosen.
5. 'B' was the target and the session a
Sargent said he had done the randomization
because Harley asked him to. Sargent said he had removed a 'B'
because it was bent and therefore distinguishable from others. He
said he had already told Harley about this. Harley now said he
remembered being told although he had not remembered this previously
when he and I discussed the problem.
Sargent said there was no harm in him coming
into the judging since he did not know the identity of the target,
even though he had done the randomization. He denied 'pushing' the
There are therefore two hypotheses to consider.
The hypothesis of cheating led to the discovery of the errors. It
explains them fairly neatly and could, if extrapolated to the whole
experiment, account for the large effects observed'.
The alternative is ad hoc, and cannot
account for the large effects (these would have to be attributed to
psi). It would imply a good deal of carelessness in the running of
I considered that the evidence was not
conclusive in favour of either hypothesis and that more evidence was
needed. I did not wish to make any accusation, or even implication,
of cheating, without conclusive evidence that it had occurred. It
therefore seemed essential to gain further information which might
support one or other hypothesis, and in the meantime not to
publicise the findings.
There were several kinds of information which would
1. Further observations of the experiments in
progress. These were planned for a second visit of three weeks early
in 1980. However, two weeks after I left Cambridge, Sargent informed
me that he did not wish me to return, which of course I accepted.
2. The results of further experiments using the
same procedure and subjects, but a different experimenter. This was
also part of our original plan, but did not take place for the same
3. A full report by Sargent (and his colleagues) of
their explanation of the errors.
In January 1980, I wrote a report for the SPR
archives. This was to be available to SPR members on request, but I
hoped it would soon be made redundant by a published version.
Sargent and I agreed that we would each write our own version of the
events. I wrote mine and sent it to him. He wrote an early
(confidential) version, but never produced a final one. He continued
to promise he would and therefore I waited and did not publish my
When it became clear that Sargent was unlikely
to produce a report, I discussed with Harley the possibility of
publishing a joint account. We differed in some respects but agreed
that we could write a report together if the points of disagreement
were made clear. Harley did not write a report. I finally concluded
that no written explanation was likely to be forthcoming from either
Sargent or Harley.
4. Further analyses of raw data from previous
There were several ways in which the raw data might
help to test the hypotheses. For example, according to some methods
of cheating one would expect the most popular picture in any set to
have been target more often than predicted by chance. I asked
whether I could check this. However Harley said that the pictures in
each set were changed from time to time, without any record being
kept, and that it would be impossible to check this from the
Another hypothesis was that, if one person were
cheating and pushing the subject towards the target, rejudging
should give poorer results than the original ones. This would be
easy enough to do and Sargent said that he intended to do it.
However he never published the results of any rejudging.
Thirdly, if one person were cheating, the most
significant results should occur when they were acting as agent or
experimenter, though of course this could also occur because of a
psi-mediated experimenter effect. In fact there is evidence that
scores were higher when Sargent took part in the few sessions
observed during this visit and in published data (Ashton, Dear,
Harley and Sargent 1981).
I hoped to be able to check the entire data
base for this effect. This would mean having the Blue data book in
which the names of all participants are recorded.
Finally, another suggestion was made by Parker
and Wiklund (1982). Cheating could take place by manipulation of the
randomisation combined with knowledge of the subject's likely
responses (as in 2a-c above). The easiest way to find this out is by
looking at the subjects' responses on previous trials. Wiklund and
Parker suggested that in those trials where Sargent was responsible
for the randomisation, and the subjects did not make direct hits,
there would be above chance scoring if the target were matched with
the subject's mentation on a previous trial (Parker and Wiklund).
This could be checked from the raw data and they therefore asked
Sargent for those data.
These suggestions provide definite ways in
which the implications of cheating could be lifted. If Sargent
supplied the raw data other researchers could check them for these
effects. If these effects were found, that hypothesis would be
strengthened. If they were not found then the cheating hypothesis
would lose much of its force.
I kept hoping that this would happen and the
truth become clearer. However Sargent refused to make his data
available. Several informal requests for the data were made. Then
when these failed to elicit any data, official requests were made
through the Parapsychological Association. Sargent still did not
supply the data, nor any reason for withholding them.
In 1984 the PA Council asked Martin Johnson to
head a committee to investigate the case. The final report of this
committee is now available. Council reprimanded Sargent for failing
to respond to their request for information within a reasonable
In view of this lack of cooperation it is not
possible to test any of these hypotheses against the data. Also
there now seems little hope of obtaining any new evidence and
therefore we must assess the case on the basis of what evidence we
I have been criticised for not publishing a
full account earlier. I hope I have now made clear my reasons. I did
not wish to publish something which discussed the hypothesis of
cheating, (a) while there were still promises that others would
supply alternative explanations for my findings and (b) while there
was still some hope that further evidence would come to light.
I think there is still doubt as to the correct
hypothesis. However, any hope that this will be speedily resolved
now seems to be unrealistic. I am therefore presenting the
evidence I have, as accurately as possible. I hope that others will
add their versions to mine.
There has recently been considerable
controversy concerning the value of the ganzfeld database in
providing evidence for psi. The many experiments involving Sargent
as experimenter form a very substantial and important proportion of
that database. According to Hyman (1985) Sargent's 9 studies and
Honorton's 5 account for one third of the total. According to
Honorton (1985) Sargent's experiments have the second highest effect
size, after Honorton's own.
If Sargent's findings were removed from this
database it would be considerably weakened as evidence for psi.
Brain and Perception Laboratory
of Bristol, Bristol.
Ashton, H.T., Dear, P.R., Harley, T.A. and
Sargent, C.L. (1981) A four-subject study of psi in the ganzfeld.
Journal of the Society for Psychical Research, 51, 12-21
Blackmore, S. J. (1980). Extrasensory
Perception as a Cognitive Process. Unpublished PhD Thesis,
University of Surrey.
Honorton, C. (1985). Meta-analysis of psi
ganzfeld research: A response to Hyman. Journal of Parapsychology,
Hyman, R. (1985). The Ganzfeld Psi Experiment:
A Critical Appraisal Journal of Parapsychology, 49 3-49
Parker, A. and Wiklund, N. (1982). The
ganzfeld: A methodological evaluation of the claims for a repeatable
Sargent, C. L. (1980). Exploring Psi in the
Ganzfeld. Parapsychological Monographs No 17
Sargent, C. L., Harley, T. A., Lane, J. and
Radcliffe, K. (1981). Ganzfeld psi optimization in relation to
session duration. Research in Parapsychology 1980, 82-84.
Sargent, C. L. and Matthews, G. (1982).
Ganzfeld GESP performance in variable duration testing. Journal of
Parapsychology 1981, 159-160
I wish to thank Dr. Carl Sargent for inviting
me to visit his laboratory, and the Society for Psychical Research
for financial support.
See also the following responses published in the same journal
Harley,T. and Matthews,G. (1987) Cheating, psi, and the appliance
of science: A reply to Blackmore. Journal of the Society for
Psychical Research, 54, 199-207
Sargent,C. (1987). Sceptical fairytales from Bristol. Journal
of the Society for Psychical Research, 54, 208-218.
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