THE NEXT step is to find, if possible, any special conditions or test procedures
which limit ESP performance. To do so requires a survey of the general
conditions, as far as they have been discovered, under which ESP occurs and of
all special conditions found to affect score averages either favorably or
The ESP results available represent many researches, done largely without
co-ordinated attack, upon the problems here considered. There is naturally some
difficulty in finding a plan of presentation that co-ordinates these various
conditions. There are, however, certain more cognitive aspects to the various
test situations; there are different modes of response in the tests, varieties
of social situation, and miscellaneous ways of affecting motivation, ways that
induce positive and those that evoke negative deviations.
Cognitive Situation [top]
Two sets of special conditions to be considered in this chapter belong under
this general heading; the effect of the so-called "trance" state is one, and the
other is the effect of number of possibilities for a choice, or the p-value* on
* = probability of success in each trial.
Trance(1). The discussion under this heading includes both self-induced and
hypnotically-induced trance. The former is of particular interest because of the
general association in the public mind between self-induced trance and ESP,
owing to the fact that many professional mediums go into trance (or appear to do
so, at least) before attempting to divulge information supposedly arrived at
extra-sensorially. Also, as indicated in the preceding chapter, the hypnotic
state and ESP performance have been associated historically since the days of
Mesmer and his followers.
(1) A state of withdrawal of attention to (or responsiveness to) environment,
with (usually) the exception that special rapport is maintained with a given
individual (hypnotist, "sitter").
Hypnotic Trance. The amount of work done with a subject in the state of
so-called hypnotic trance, conducted with the assistance of Lundholm and
reported by Rhine(2), indicated that this state as induced by them was not
successful for the subjects tested in bringing out any significant evidence of GESP ability. The results obtained were slightly positive in trend, but they are
reported as being no more so than those obtained with the same and with other
subjects in tests in the normal state. In a number of the earlier investigations
of ESP, particularly in France and England(3), the hypnotic state
was used and success was assumed to be associated with that state. There were,
however, no adequate controls made as to what might have been obtained from the
same subjects in the normal condition. This consideration, taken together with
the fact that equally remarkable results have since been obtained on other
subjects by other experimenters with the subjects in the normal state, suggests
that hypnotic trance is not necessarily advantageous to experimental success(4).
The word "trance" is not a very precise term and no acceptable criteria are
known as yet for the determination of measure of the state whether self-induced
or induced by suggestion. The above discussion is necessarily subject to all the
reservations that attach to the term used.
(2) Rhine, J. B. Extra-Sensory Perception.
Boston: Bruce Humphries, 1934.
(3) See; Myers, F. W .H. Human Personality and Its Survival of Bodily Death.
London: Longmans, Green, and Co., 1903, 2 vols.
(4) In later work at the Duke Laboratory, Zirkle and Ownbey hypnotized three
subjects, giving them, in all, 105 runs in the normal state before hypnotic
state was induced, and 105 runs during the trance. The control average was 5.11
and the average during the trance was 5.55. The average during the trance is
significant in critical ratio, but the difference between the two blocks is not
significant. The results are inconclusive, in any case, in view of the fact that
the subjects were not naive. They knew that the Purpose of the experiment was to
obtain higher scores during the trance than before. The 5.55 average obtained
during the trance was not above their normal average. The normal control of 5.11
was, in fact, below it.
Self-Induced Trance. Performance of trance mediums, as mentioned, have given the
general impression that the ESP capacities involved in trance are very different
from those possessed by the subject in the normal waking state. While adhering
strictly to the ESP procedures, Rhine(5) studied the performance of a
professional medium whom Pratt(6) found capable of demonstrating, under very
well controlled conditions, unaccountable knowledge approximating (in type) that
shown by the medium in her routine professional practice. In the Rhine
investigation, the medium was subjected to routine telepathy and clairvoyance
tests both in the waking state and in her customary self-induced trance with a
purported spirit personality assuming control of her body. The results reported
were approximately the same for the trance as for the waking state, being only
slightly lower in the former, both in telepathy and clairvoyance tests. A wide
discrepancy between score averages in telepathy and clairvoyance was shown in
both the waking and the trance state, and the same trend in scoring was shown in
both methods and for both personality states (see Graph 1, below).
(5) Rhine, J. B. "Telepathy and Clairvoyance in the
Normal and Trance States of a 'Medium'," Character and Personality, III
(6) Pratt, J. G. "Toward a Method of Evaluating Mediumistic Material,"
Bulletin 23, Boston SPR, 1936.
Comparison of Scoring Rates in Trance and Normal States
Chronological comparison of scoring rates in telepathy (T) and in
clairvoyance (C) by the trance personality U and the normal personality of
Mrs. G. The points represent the score average of 3-day periods from A to
(From Character and Personality,
1934, 111, p. 107)
This is the only study of this nature in which extra-chance results were
obtained. A series of tests which were given the same subject a year later by
Rhine(7), using pre-shuffle card-calling tests (which had been successful
with other subjects), yielded only chance results. Still later a series by Goldney and Soal with this medium, using GESP and PC procedures, is reported to
have given chance. Yet the medium was still able to go into trance. It can at
least be stated that it is suggested that the self-induced trance, like the
hypnotic, is neither essential nor apparently advantageous in the ESP test
performance. Some experimenters find that their subjects approach a light trance
in their effort at concentration. Whether this is essential or is only important
because the subject believes it to be so has not been determined and remains an
(7) Rhine, J. B. "Experiments Bearing on the
Precognition Hypothesis," Journal of Parapsychology, II (1938), 38-54.
Number of Choices, or p-Value. The second topic under cognitive relations has to
do with the possible effect upon performance of the various numbers of
possibilities which the subject has to keep in mind in the tests. These numbers
represent the p-value. If p = 1/2, there are, of course, only two symbols or
objects to which response is to be made. If p = 1/25, the task of judgment is
presumably burdened with the necessity of keeping cognitively available as many
as possible of the 25 objects relevant to the judgment. The question is: Have
these differences any effect upon scoring?
It might logically be supposed that the number of available possibilities (hence
the p-value) in the ESP test should be the number most conveniently kept in the
foreground of awareness. In fact, the primary reason why a range of five symbols
(or p = 115) was made the basis of the experiments reported by Rhine(8) was
that most people can readily retain five symbols and that fewer than five
symbols would tend to make fixed habits of patterning more likely than would the
larger number. Although this was decided on theoretical grounds, its merits may
now be tested quantitatively. With the introduction of a formula for the ESP
quotient (per cent of trials most probably attributable to ESP alone, chance
hits excluded) by Foster, there is made available a means of comparison of
rates of scoring on trials with different p-values. Such comparisons are shown
in the ESP quotients of Table 18 (below). These are obtained from the totals for the
different p-values given in Table 5, the items being reproduced with appropriate
(8) Rhine, J. B. Extra-Sensory Perception.
Boston: Bruce Humphries, 1934.
I. Results Obtained with all p-Values having over 10,000 Trials
A. Total Results
B. Results Reported by Academic Men
TABLE 18 - Continued
II. Results Obtained with all p-Values having less than 10,000
A. Total Results
B. Results Reported by Academic Men
Since this comparison is of very general character and is made on groups of
results obtained by different experimenters with different subjects, and with a
diversity of other conditions, it is recognized to be hazardous to base
conclusions on it. In the interest of a more uniform comparison, however, those
p-values which have over 10,000 trials are selected to make Section I-A of the
table. This will insure that a greater number of series, subjects, and
investigators be included in each item, and should make any comparison more
representative and correspondingly safer. Also as a further step toward getting
a more uniform basis for comparison, the results obtained by investigators of
the psychological and academic groups segregated in Table 4 have been treated
separately, again subject to the minimum of 10,000 trials, and the ESP quotient
is given for each item of this selection (in Section I-B). (In Section II of the
table are given the p-values with smaller series, ranging from 41 trials to
3,259 and in p-value from 1/3 to 1/100. These are mostly represented by a single
report each, all by earlier work, and frequently by a single subject in each
series. Any conclusion as to relative merit of p-values from these data would be
hazardous; they are presented to complete the record.) It will be seen that
there is no important difference between the ranking of p-values and quotients
of this more selected group of experiments and the general total, and that fact
is itself of interest. From this section of the table, it will be seen that in
both sub-sections, A and B, the highest ESP quotient is found for p = 1/5 and
that in both directions from this value the quotient falls away.
There is an interesting exception to the trend, however, in the case of p =
1/10. Here we have to do with perhaps the most familiar of all symbols, the
cardinal numbers, and here presumably we have the factor of familiarity reducing
the cognitive burden of the subject in keeping all the elements of possible
choice before his attention. It might, indeed, be wished that a more deliberate
experimental study of this point were available for the comparison under
discussion, but the analysis just made nevertheless leaves it clearly suggested
that 1/5 is the most advantageous p-value. It is more speculatively suggested
that ease of retention combined with maximum of variety together make 1/5 the
best range of choice.
of Response [top]
Matching and Calling. With reference to the overt expression of ESP judgments,
it is again profitable to refer to nonexperimental origins. There have been
developed in the various practices of the occult (in which ESP might be
involved) two general types of response: One of these consisted of oral
communication of information supposed to be revealed through hallucinations,
more commonly visual (exemplified in the use of the crystal ball) but sometimes
auditory (represented in the experiences reported of Socrates and Joan of Arc).
The other type consisted of motor, usually manual, movements such as those
involved in the Ouija board, the exploratory pendulum, the dowsing rod, and the
planchette and automatic writing.
The experimental invasion into this field of questions has followed these two
general lines. There has been, on the one hand, considerable work done with test
procedures which depend upon manual response by the subject in registering his
judgment. The various matching methods and ESP shuffle, as well as Tyrrell's
machines, represent this type. In the calling methods, on the other hand, the
subject registers his mental impression (hallucination, image) orally or in
writing. It has been established that ESP performance is obtainable with either
of these two lines of response: either with matching methods such as those used
in the Pratt and Woodruff series, as well as a number of others; or by the
originally more common method of mentally choosing the card and either writing
it down or calling it orally to a recorder. The greater number of series of
tests under the best conditions were done by the latter method, more commonly
with the subject writing down his own responses.
Comparison of the test performance for the matching and calling procedures has
reached the point at which it can be said to be indicated that one is as
successful as the other. Tyrrell(9) obtained with his pointer apparatus an
average of 6.26 per 25; with the electrical machine, 5.90; and in 1,000 card
trials, 5.70. Card trials were of the calling procedure, whereas the responses
made on the two types of apparatus were manual. Tyrrell points out that his
subject does not usually do as well during the initial stage of a new procedure
and there may be some allowance made on that account for the slightly lower
average made on the card trials. Tyrrell emphasizes the greater cognitive
activity involved in calling the cards which he thinks may be unfavorable for
some subjects. Woodruff and George made a study of the two types of response in
a series offering a closer comparison. They compared the same subject on BT*
tests and two kinds of matching, OM** and BM***. They found that the choosing and the
(oral) calling response of the BT method showed very little difference from the
averages obtained from OM. With BM, however, which presumably involves less of
conscious experience as a basis for judgment, the average was lower than it was
for either BT or OM. The Woodruff and George experiment consisted of two
sections: that done with the use of screens, and that which was unscreened. The
same relationship held in both of these divisions. The bar graph shown below,
from the Woodruff and George report, gives a convenient summary of the results
of interest here.
* Before Touching. The technique in which the top
card of the face-down deck is called and, after being called, is laid aside for
checking at the end of the run. Each card in the deck is treated in the same
** Open Matching. The technique in which the subject matches a deck of ESP cards
to five key cards which are face up before him.
*** Blind Matching. The technique in which the subject matches a deck of ESP
cards to five key cards which are laid face down before him in an unknown order.
Unless otherwise stated, the order is also unknown to the experimenter.
(9) 322 Tyrrell, G. N. M. "Further Research in
Extra-Sensory Perception," Proceedings of the Society for Psychical Research,
XLIV (1936), 99-168.
Comparison of Test Procedures
and George's comparative results from OM, BT, and BM tests with screened
cards (black bar) and unscreened cards (white bar).
(From Journal of Parapsychology, 1937,
1, p. 23.)
Gibson's results fairly closely approximate those of Woodruff and George, using
GESP results as a substitute for BT, since Gibson did not use the BT method.
Table 19 (below), reproduced from Gibson's paper, offers a comparison of the two sets of
results. Price(10) likewise found matching methods and calling methods to be
approximately similar in score averages.
(10) 220 Price, Margaret M. "A Comparison of Blind
and Seeing Subjects in ESP Tests," Journal of Parapsychology, II (1938),
Comparison of Independent Results
Woodruff and George
||Av. per 25
||Av. per 25
So far, then, as to whether there is any great difference between calling (BT or
GESP) and matching methods (OM), the evidence is thus far negative. The fact
that the more remarkable series, such as that of Riess, was done by the calling
procedure, while matching methods used by Pratt and Woodruff yielded only a 5.2
average, superficially suggests a difference that closer and more comparative
study does not bear out.
DT and BM. Before leaving the question of the relative merits of ESP methods,
the question of the lower level of scoring in DT than in BT (or GESP), and in BM
than in OM, deserves consideration. With but one exception(11), and
that not involving a great number of trials, BM averages below OM, DT below BT.
This may be rated as indicated on the basis of the work shown above in Table 19
so far as matching methods are concerned; and in DT comparisons the work of
Rhine(12), MacFarland, and Gibson confirms the lower trend of that method
compared to BT or GESP. In this connection should be mentioned the ESP shuffle
method which, though less familiar, has been tried in comparative studies
sufficiently to warrant its consideration here. In a study of children by
Pegram(13), in which OM, BM, DT, GESP, and the ESP shuffle techniques were
compared, BM, DT, and the ESP shuffle gave averages respectively of 5.29, 5.21,
and 5.21, whereas OM yielded 5.48. There were about 400 runs made with each
method. The GESP averaged 4.99, a fact which the experimenter attributed to the
circumstance that it came first in the experimental period and suffered from the
initial need of adjustment of the subjects to the experimenter. This comparative
study would appear sufficient to indicate on experimental grounds a rating of
the ESP shuffle along with DT and BM, especially in view of the fact that the
scoring that has resulted in the rather extensive work reported by Rhine, Smith,
and Woodruff, and in the ESP shuffle work of Pratt and Price more closely
resembles the DT and BM averages in general than the BT and OM.
(11) Price, Maragret M. "A Comparison of Blind and
Seeing Subjects in ESP Tests," Journal of Parapsychology, II (1938), 273-286.
(12) Rhine, J. B. Extra-Sensory Perception.
Boston: Bruce Humphries, 1934.
(13) Pegram, Margaret H. "A Comparison of ESP Test Procedures." [Unpublished
The following hypothesis is suggested to explain the lower score rating of the
DT, BM, and ESP shuffle methods. The three methods under consideration probably
do not permit as sharp a focus of attention as do the other methods with which
they have been compared. By this is not meant a poor focus of attention to
physical detail, but instead a definite mental limitation or lack of
orientation. In the case of DT, the U-curves reported by Rhine(14), Pegram,
Gibson, and Sharp and Clark - though not found by MacFarland and George or by
Martin and Stribic(15) - suggest such a difficulty in focus of attention in
the middle of the deck. This is indicated to be a mental difficulty rather than
a physical obstruction by the fact that the cards in the lower part of the deck,
which should offer (to the subject located above the level of the deck) even
more physical difficulty than those in the center, average about as many hits as
do the cards located toward the top of the deck and more than the cards in the
middle. The cards towards both ends of the runs naturally stand out cognitively
above those of the interior and are more easily located and identified with the
same acuity of attention.
(14) Rhine, J. B. Extra-Sensory Perception.
Boston: Bruce Humphries, 1934.
(15) Martin, D. R., and Stribic, F. P. "Studies in Extra-Sensory Perception: I.
An Analysis of 25,00 Trials," Journal of Parapsychology, II (1938),
In BM, as contrasted with OM, there is again less upon which to fix attention
since the five key cards are no longer visibly presenting themselves to render
the choice vivid for the subject. Their standing out in OM presumably
facilitates the focusing of attention. Likewise in the ESP shuffle, the effort
at concentration of attention upon a given card objective is greatly frustrated,
more so perhaps than in any of the tests. It is only a broad, dull, and very
vague focus that can be achieved at best. On the other hand, in GESP, BT, and
PT, even though there is not sensorially present any key card for the assistance
of attention, there is the temporally and physically isolated event as a target
upon which the subject can concentrate in the act of making his response.
Group Tests with Adult Subjects. In searching for relations between the text
situation and ESP performance, the presence of other persons in the subject's
field of experience appears to be important. In fact, somewhat more positive
statements can be made in this connection than has been true of the questions
raised earlier. One of the most important of these problems is that of the
relation of isolation of the subject during the test. The evidence shows that it
is established that the testing of the adult individual in isolation is, with
present test procedures, superior to group performance. It might even be
inferred that successful extra-chance results in group tests of adults are not to
be expected with present techniques although new conditions and methods may
succeed where the old ones have thus far failed.
The class tests reported by Rhine(16) from the Duke Laboratory yielded only
chance results. Sharp and Clark, and later Rothera(17), likewise obtained
chance results when testing groups. Sharp and Clark made comparisons of
individuals who had participated in group tests. However, the individual tests
gave significant deviations, while the group test did not. These results, taken
together with the fact that the case for ESP has rested entirely upon individual
tests with the subject working alone and with not more than two experimenters
present, appear to warrant the rating given above of the experimental
establishment of this difference with adult subjects between individual and
(16) Rhine, J. B. Extra-Sensory Perception.
Boston: Bruce Humphries, 1934.
(17) Rhine, J. B. "Rothera Experiments," Journal of Parapsychology, II
Group Tests of Children. A distinction is indicated, however, between the effect
of the group upon children and adults. L. E. Rhine and Price and Pegram have
described successful ESP performance with child subjects taking the tests in the
presence of their playmates. In such instances the whole procedure is much like
a game. Children already accustomed to playing with one another appear to be
relatively uninhibited by each other's presence. Also, Bond gave GESP tests to
22 fourth grade children in the schoolroom, with significant results, and Richet(18) refers to an anonymous schoolmaster who gave similar tests to his
pupils with successful results.
(18) Richet, C. Thirty Years of Psychical
Research. New York: The Macmillan Co., 1923, p. 91.
Visitors. It is indicated that the presence of a visitor unoccupied in the
conduct of the test will adversely affect the scoring of the subject, presumably
through distraction of attention and motivation. This observation was first made
by Lodge(19), it was confirmed by Bender(20), and experimentally demonstrated
by Rhine(21). Brugmans and Rhine both observed certain improvement in scoring
with the isolation of the subject even from the experimenter's presence. It
should be mentioned that in each case the subject was an adult, thoroughly
experienced with and deeply interested in the research program. The case might
well have been different with a child subject or with one whose interest was
less intense. In such case, isolation might lead to a decline of interest.
(19) Lodge, Oliver J. "An Account of Some
Experiments in Thought-Transference," Proceedings of the Society for Psychical
Research II (1884), 189-216.
(20) Bender, Hans. Zum Problem der Ausserinnlichen Wahrnehmung. Leipzig:
Johann Barth, 1936.
(21) Rhine, J. B. Extra-Sensory Perception. Boston: Bruce Humphries,
Subject's Relation to Experimenter. That the subject-experimenter relationship
is important in ESP tests has been suggested in the work of a number of
observers in the history of ESP. Sharp and Clark pointed out that different
experimenters obtained different results with the same subjects. One
experimenter consistently obtained only chance scores, while another fairly
consistently got extra-chance scores with the same subjects. The most successful
experimenter, too, obtained considerably lower scores than usual during a period
of intense strain and worry occasioned by the severe illness of a member of his
family. Pratt and Price brought the question of the subject-experimenter
relationship to an experimental focus, and their results indicated that this
relationship may well determine success or failure for the subject. Following
upon a long series of chance results by one experimenter and a long series of
extra-chance results by the other, the two experimenters collaborated first
under a procedure laid down by the experimenter who had previously been
unsuccessful. The results during that regime were still unsuccessful so far as
statistical significance of results was concerned. The successful experimenter
then took complete charge of the relations with the subjects although the other
experimenter was continually present and was equally responsible for all the
safeguards. The results during this period rose to the level customary for the
more successful experimenter and to a significant critical ratio as well.
In the Pratt and Price study, the experimenters were present in the room in
which the tests were given. In MacFarland's investigation, the subject was
isolated and a signalling system was used. Two experimenters were at the other
end of the communication system, which was several rooms away on a different
floor. In GESP and in DT tests, both experimenters had packs of cards and both
packs were set up as targets for the subject. One experimenter consistently
obtained higher scores for his pack than did the other, even in the DT series.
In fact, the second experimenter obtained results but little above expectation.
The experimenter who succeeded was nominally in charge of the experiment and
presumably had more prestige. He also was more experienced in the research. That
these considerations, however, are not sufficient as explanation for all cases
is shown by the fact that the opposite was true in the Pratt and Price study,
the more successful experimenter being younger, less experienced, and less
dominant in the experimental situation.
It is obvious that much remains to be discovered as to the proper
subject-experimenter relationship and a generalization will be difficult. But it
has been indicated that the experimenter's relation to the subject is a
determining condition in ESP performance. This much can be said without
attempting to define more closely just what in a given situation the
accompanying relationship actually was.
Favourably Affecting Motivation [top]
Some of the conditions already considered may well have affected motivation,
especially those under the heading of social environment. Those now taken up are
perhaps better called miscellaneous conditions presumably affecting performance
through the subject's motivation.
Novelty of Material. Among the conditions indicated as affecting ESP
performance, there is the previously mentioned work of Pratt and Woodruff in
which it was found that novelty of the materials used, consisting of the
introduction of different sizes of the ESP symbols, was associated with better
performance. This was true regardless of size of symbols and is an instance of
apparent dominance of the psychological over the physical differences. An
investigation by Zirkle, conducted with Rhine's subject, H. P., after the latter
had suddenly lost his capacity for high scoring, confirms the advantage of
novelty in test performance. The subject was given a series of 272 runs with 21
different experimental conditions, the aim being to change from one to another
as soon as the subject appeared to be bored with the method. The variations in
technique were often small, such as staring at a fixed point, looking into a
crystal ball, following a rhythmic tapping, or walking about the room during the
tests. The results of each experimental condition were divided as nearly as
possible in the middle, and the average determined for the first half and the
second half of the 21 series taken together. The average for the first half was
5.44 and for the second half, 4.90. The difference is significant.
Rewards. The effect of rewards, too, has been
investigated in experimental series, and it is indicated to be a positive one.
Woodruff and George introduced small rewards (movie tickets) during one month in
the midst of a four-month series. They found that the scores in general were
improved to a significant extent during the month when the rewards were offered.
For example, the critical ratio of the month preceding was 9.54; that of the
month during which the rewards were given, 16.25; and that of the month
following, 6.3. Approximately the same number of trials were made each month,
thus making these critical ratios comparable. During the month in which the
rewards were used, they were offered for only two weeks out of the four. There
was, however, no significant difference between the reward weeks and the
non-reward weeks. Accordingly, if the rewards are to be associated with the
greater success obtained during the month, it can only be on the ground that the
introduction of rewards brought in a different experimental atmosphere, perhaps
making the experiment as a whole more interesting even to the degree that the
control week was itself subject to the general effect. Most important, perhaps,
on the speculative aspect of this experiment, is the possible competitive spirit
that was introduced by offering a reward only to the winner(22).
(22) In an experiment conducted by Rhine in "The
Effect of Rewards upon Performance in ESP Tests." [Unpublished MS], a similar general enhancing
effect was obtained, but with the same lack of specific relation to the actual
period of application of reward. That is, if favorable results are to be
attributed to the use of rewards, it is as if the effect is not well localized,
but spreads to the entire experiment during the series in which rewards are
Price and Pegram and L. E. Rhine used candy or some form of refreshment in their
experiments with children. There was, however, no control as to the effect
except an incidental one when Pegram(23) mentions that once she forgot to
provide the candy, and on that occasion the results were the lowest of the
series, being somewhat below chance.
(23) Pegram, Margaret H. "An Investigation of ESP
Ability with Mentally Deficient Children." [Unpublished MS].
Competition. The competitive condition was mentioned above as a possible factor
in the Woodruff and George results. Price(24), using carefully screened open
matching, made a definite study of the relative value of competition with 25
children as subject. Three conditions were used: first, the subject working
alone; second, two subjects working together, but in such a way that each had no
concern with the results of the other (the checking was done in a manner that
did not permit easy comparison); and the third condition, competitive - the two
subjects working opposite each other and expecting to compare scores at the end
of each run. In the solitary situation, 220 runs were given, resulting in an
average of 5.2; 250 runs in the social situation averaged 4.5; 220 runs in the
competitive situation averaged 6.5. The competitive tests gave not only the
highest result, but the only significant one. This indicates that competition
affects favorably ESP scoring by children. It might be suggested that the
competitive condition was the one which would appear to the children as most
like a game, and hence the one in which they would feel most spontaneous
interest. It is of interest to note that the apparent effect of competition did
not "spread" as did that of reward, though it is not clear why this difference
should have occurred. It is plain that these effects raise further problems.
(24) Price, Margaret M. "An Investigation of the
Effect of Competition in ESP Tests with Children." [Unpublished MS.]
Conditions Adversely Affecting Motivation
Under this title is introduced work indicating that unusually long runs, delay
in checking and scoring, mechanical timing of rate of response at an abnormal
pace, and highly routinizing experimental procedures will inhibit ESP.
Long Runs. Richet(25) pointed out that long runs were a hindrance to good
scoring and submitted experimental work to show that when the run was
excessively long (over 100 trials) the hits were relatively few. Estabrooks
reported better success in the first 10 of 20 trials. Rhine(26) found that
runs of 50 and 100 trials gave definite decline curves. Sharp and Clark compared
DT* 25 with DT 75 and DT 125. While the averages are not given, inspection of
their Graphs 3 and 4 shows that the longer runs averaged below the shorter one
of 25. This relation is indicated, although there is much to be learned yet
about the relative length, rate, and other circumstances of the test before the
relation is at all clearly understood.
* Down Through. The technique in which the cards are
called down through the deck before any are removed or checked.
(25) Richet, C. Thirty Years of Psychical
Research. New York: The Macmillan Co., 1923.
(26) Rhine, J. B. Extra-Sensory Perception. Boston: Bruce Humphries,
Delay in Information Regarding Scores. The first suggestion that delay in
checking might inhibit scoring came from an investigation by Pratt(27). Rhine(28) found in the analysis of work conducted with sealed opaque envelopes that
when the results were separated into three conditions: (a) immediately checked,
(b) brief delay in checking (that is, less than 24 hours), and (c) long delay in
checking (24 hours or longer), that the score average declined from the first to
the third of these conditions. They were significantly positive in the first,
slightly positive in the second, and significantly negative in the third. A
negative effect with delay in checking is thus indicated.
(27) Unreported, except as pooled total, because conditions lacked something in
completeness. It is mentioned here with the reservation expressed in
Chapter X (Introduction: Relations and Evidence).
(28) Rhine, J. B. "ESP Tests with Enclosed Cards," Journal of Parapsychology, II
In addition to the delay in checking and informing the subject of his success,
there were other conditions that might have contributed to the negative
deviation. The sealed opaque envelopes used were sent to the subject by mail,
and were used over and over again, the subject sending the record of his calls
together with the code number on the envelope back to the experimenter for
checking. Along with the delayed checking, there should be considered other
conditions which might have contributed to a general feeling of frustration on
the part of the subject. While Riess's subject was never told of her scores,
even after the experiment was finished. she was presumably confident of her
ability to begin with, by reason of earlier experiences, and was told each time
that her work was interesting - i.e., the encouragement was simply not
numerically expressed. Rhine's subjects were told that much too, but the receipt
of the information by mail and only after several days had elapsed, may make all
the difference between frustration and encouragement.
Formality of Procedure. Rhine(29) reported in 1934 a total of 18 out of 27
subjects, given at least 100 trials in individual tests, as having given a
critical ratio of 2.5 or more. On the other hand, in a later series by Ownbey,
Pegram, and Rhine, mentioned above, with the same safeguards and using the
method that had been most successful in the earlier work, 43 subjects were each
given, on the average, 425 trials with routine schedule and formal procedure.
Out of these 43, only one subject approached the critical ratio of 2.5. The
three experimenters involved had each obtained significant results with other
subjects in earlier work. The only known difference was the fixed routine and
the atmosphere of an experimental task rather than an informal game. Pratt and
Price found the more informal manner of handling their child subjects was the
more successful of the two sets of conditions used. L. E. Rhine referred to the
advantage of a spirit of fun. Barrett, nearly sixty years ago(30), said. "But of the favorable effects of freedom from constraint and of a spice of pleasurable
excitement, we can speak with entire assurance"(31). Many warnings may
be found in the literature on ESP against restraint, formality, over-seriousness,
and interference with spontaneity (this need not be confused with relaxation of
caution). Pratt and Woodruff report an average of 5.34 with Woodruff working
alone, and an average of 5.20 with both experimenters present and with an
elaborated routine that requires considerable space even to review. In view of
the fact that both common sense and what is known in psychology would lead to
the expectation that an easily inhibited process would function best under
informal conditions, and in view of the general agreement of expression by
experimenters concerning this point, the experimental work is sufficient to
warrant the rating of indicated for the hypothesis that formal routinized tests
are less successful than the more game-like procedures with the same degree of
(29) Rhine, J. B. Extra-Sensory Perception.
Boston: Bruce Humphries, 1934.
(30) ISS note: This article was written in 1940.
(31) Committee on Thought-Reading, SPR. "First Report," Proceedings of the SPR,
I (1882), p. 29.
Frustration. Rhine(32) pointed to the negative effect of frustration of the
subject by prevailing upon him to continue the tests when he was strongly bent
on leaving. His subject A. J. L. had been making, for the preceding 600 trials,
an average of 9.9 (ESP Q = 25); but upon reaching the time arranged for his
departure, persuasion to participate further against his will was accompanied by
a drop to an average of 4 for the next succeeding 400 trials (ESP Q = 20)(33). Estabrooks obtained positive deviations that were significant in his first three
series. In the fourth, he asked subjects who had taken part in one series to
participate in another in which they were taken to a still greater distance with
four closed doors between them and the agent. The deviation was significantly
negative (C.R. = 2.7 for suit; 640 trials). Estabrooks himself appears to have
expected decline with distance. If the subjects felt as he did, the experiment
provided excellent frustration conditions. Negativistic motivation may
reasonably be supposed to result from undertaking a seemingly impossible task
under mere constraint of courtesy. This work points the way not to a conclusion
but to an experimentally suggested relation and to the need of further
experiments in its verification.
(32) Rhine, J. B. Extra-Sensory Perception.
Boston: Bruce Humphries, 1934.
(33) Assuming that frustration induces negative direction of effort, the subject
may be expected to miss the card instead of hit it when frustrated, if ESP
operates at all. Hence, if experimentally induced, the results may be treated as
low-aim tests and the formula for low-aim ESP Q applied (Q = 20D, where D is the
Mechanical Restraints. Any mechanical restraint in the achievement of a delicate
judgment might be expected to interfere with success.
Mechanically Fixed Tempo. That the restraint of a fixed rate of response may
adversely affect the ESP judgment has been indicated by Stuart's(34) tempo
experiments. In these the timing of the subject's response was fixed by a
metronome, and the rate of response varied from one run to another, above and
below the normal or favorite tempo of the subject, as ascertained at the
beginning of the sitting. Blind matching and screened touch matching methods
were used. The results showed that when the rate of response was fixed at that
which was normal to the subject, successful ESP performance was possible, but
when the rate was abnormal, only chance results were obtained. A mechanical
restraint upon movement, either in speeding up or slowing down beyond the
subject's normal rate, was found to be inhibitory.
(34) Stuart, Charles E. "The Effect of Rate of
Movement in Card Matching Tests of Extra-Sensory Perception," Journal of
Parapsychology, II (1938), 171-183.
The Effect of Drugs
The narcotic drugs, alcohol and sodium amytal, and the stimulant, caffeine, have
been used in ESP experiments. Several hypothetical relations between drugs and
score effects are experimentally indicated.
Small Amount of Alcohol. It should be remembered that the effect of narcotic
drugs is in general very dependent upon the amount administered and upon the
individual taking them. Small amounts give results which in some respects are
opposite to those of larger doses. Brugmans reports getting the best results of
his series after the subject had been administered a small dosage of alcohol (30
grams). The 29 trials given following this dosage gave an ESP quotient of 75,
which is almost of the order of Riess's remarkable series (ESP Q = 91). The 38
hits of the other 151 trials in Brugmans' series gives the much lower quotient
of 18. The amount of alcohol given the subject presumably was too small to have
adversely affected the acuity of discrimination, but it may have been sufficient
to add not only to the agreeableness of the experiment but to the relaxation and
abstraction from surroundings regarded by most experimenters as important in ESP
tests. The importance of this relaxation and the passive state of mind was
emphasized by Brugmans himself. His interpretation is that the alcohol
counteracted the normal inhibitions.
Sodium Amytal. Rhine(34) reported in 1934 the results of experiments with two
subjects using the BT procedure, and with one subject using the PT* procedure, in
which large doses of sodium amytal (6 to 15 grains) were used. All three
subjects were given the drug after lengthy preliminary series which permitted an
estimate of scoring levels in the normal state. Two subjects were informed what
drug they were given, but had no knowledge of its effect beforehand. The third
was informed that the drug in capsule form might be either caffeine or amytal.
In all three cases, the score average dropped abruptly and to a striking degree.
The subject given the largest dose, 15 grains, dropped to chance average.
* Pure Telepathy. The word "pure" emphasizes
the exclusion of clairvoyance.
(34) Rhine, J. B. Extra-Sensory Perception.
Boston: Bruce Humphries, 1934.
Confirmatory results were obtained by Clark and Sharp(36) using the screened
touch matching procedure. Subjects were not informed as to which of three
capsules they were given: sodium amytal, caffeine, or a control.
(36) Unpublished report.
Caffeine. Rhine(37) reported the use of caffeine with one subject on occasions
following depressed scoring and the report by the subject that he was drowsy or
fatigued. Comparison of scores before and after administration of the drug
showed a significant difference. Another subject, working with the PT procedure,
was administered a 5-grain dose of caffeine citrate in capsule form following
three hours after a 6 grain dose of sodium amytal which had produced a highly
significant drop in score average. The effect of the administration of caffeine
on a 300-trial series made one hour after ward was to produce a highly
significant rise in score average from that of the 300 trials preceding, made
under the influence of the sodium amytal.
(37) Rhine, J. B. Extra-Sensory Perception.
Boston: Bruce Humphries, 1934.
This marked drop with the administration of sodium amytal and recovery with the
later administration of caffeine was likewise confirmed in the work of Clark and
Sharp under the more safeguarded method of the screened touch matching
1. Neither hypnotically-induced nor self-induced trance is found, in the
limited exploration thus far made, to be advantageous to success in ESP tests.
The investigations of these points are, however, limited to the extent that
these findings cannot be regarded as more than suggested.
2. It is on the other hand suggested that there is an advantage to a p-value of
1/5. Success, however, is by no means confined to that p-value.
3. Both matching and calling procedures are established as successful. It is
indicated that these are approximately equal in advantage.
4. The DT and BM methods are indicated as averaging below BT and OM. ESP shuffle
is indicated to belong likewise in the lower-scoring group.
5. It is established that individual tests are superior to group tests for adult
6. It is indicated, however, that children may constitute an exception to this
7. It is likewise indicated that visitors merely witnessing the performance of
the subjects, and taking no part in the experiment, may adversely affect
performance in the tests.
8. It is indicated that the subject-experimenter relation may be determinative
9. The following conditions presumably affecting motivation are indicated to be
of importance in ESP tests (the first three favorably, and the rest adversely):
(a) novelty of material, (b) reward, (c) competition, (d) length of run. (e)
delay in information regarding scores, (f) formalizing the procedure.
10. It is indicated that mechanical restraints limiting the subject's rate of
performance affect the scores adversely.
11. Narcotic and stimulant drugs in different doses have been indicated to have
an effect upon performance: (a) small dosage of alcohol, a favorable influence;
(b) large doses of sodium amytal, a lowering of scores; and (c) caffeine, an
effect of counteracting the effect of sodium amytal.
The article above appeared in "Extra-Sensory Perception After Sixty Years: A
Critical Appraisal of the Research in Extra-Sensory Perception" (1940, Henry
Holt and Company, New York) by J. B. Rhine, J. G. Pratt, C. E. Stuart, B. M.
Smith and J. A. Greenwood.