Extra-Sensory Perception: Part II. The Experimental Results: Chapter IV. Earlier and Minor Experiments

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CHAPTER IV

Earlier and Minor Experiments

The two-fold objective of the experiments in extra-sensory perception at Duke University is, as stated earlier, first, to answer, if possible, by mathematically indisputable evidence the question of its occurrence and of its range; and, second, to further its understanding by the discovery of its relationships to other mental processes and to the essential physiological and physical conditions. In the detailed accounts of the experiments given in this chapter and those immediately to follow (5 to 8) the first of these purposes, concerned with the proof, will be given first consideration. Then in later chapters will be summarized those special experiments which were designed to help to explain rather than to prove. Those readers who are in danger of being bored by more proof for extra-sensory perception can well afford to go over to Chapter 9 (unless perchance they may be interested in the personal accounts of the principal subjects given in the immediately following chapters).

In these chapters containing the more complete reports all the available information that seems helpful to thorough understanding will be included and will be built up around the personalities of the major individual subjects. The reason for this is that in this work so much irregularity of conditions, procedure, and results is inevitable because of the great factor of human variability that it is hard to generalize over the whole range of subjects in any detailed fashion. However, in Part III which follows this series of individual studies there will be a general discussion of the main hypotheses, in which a summary will follow, and

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The first laboratory procedure was that of the trance-telepathy experiments by Dr. Lundholm and myself. Our immediate purpose in this was to discover, if possible, any individual showing in the trance condition the striking telepathic capacity claimed for some of the hypnotized subjects in the 80's and 90's by French and English students in this field. We did not at this stage exclude clairvoyance as a possibility. We were using the hypnotic trance, however, merely as a presumably favorable condition. There was also the secondary purpose of measuring the total scores by the probability devices in order to reveal any minute and dispersed telepathic ability present. To state the outcome in a word, the first purpose was not satisfied by the experiment but the second did, I think, achieve a small degree of success.

The subjects were students who volunteered for the experiment. Dr. Lundholm and I together worked with 12 and, after Dr. Lundholm was unable to continue because of time limitation, I alone went on with 18 more. Six others were eliminated because of failure to attain the desired state of trance. With the 30 subjects in all we carried out a total of 1,115 tests, using three different procedures of testing for telepathic perception but with the same general hypnotic treatment.

i.e., np, where n equals number of trials and p the probability of success for each trial, in this case 1/10; here np=21.). This is only about 3 times the probable error and not to be taken very seriously. For the whole 530 trials made by the 30 subjects, the level of deviation is 23% above the chance expectation and has still about the same ratio to the probable error, slightly less (2.6). This is, however, barely enough to encourage further work and not enough for a conclusion.

On one of the other techniques we had poorer results, not significant in any way. This was a simple test with 2 possibilities. The purpose in

i.e., 166. This is, however, only about .6 of the probable error and is, of course, just "chance" variation.

The third type of procedure involved a still more overt response. A circle 5 inches in diameter was cut in a piece of cardboard, with the circumference marked with pencil into octants. A thumbtack was stuck in the table at the center of the circle. The subject was told that when the signal was given his second finger, which would be resting on the tack's head, would automatically move out to the circumference to that octant which the agent was fixing his gaze upon and was "willing" him to touch. There were only 245 trials of this; it was very slow work and gave only a low positive deviation from np, chance expectation; namely, 4.4, which is 14% above np but only 1.27 times the probable error. We have, then, the following little table of results:

TABLE I

Extra-Sensory Perception in Hypnotic Trance

Lundholm and Rhine, Fall, 1930

). These were mainly chosen by Dr. Zener, with a view to avoiding undue overlapping, complication and difference in familiarity. They are still in use. (We have once since substituted a "heart" for the "waves" figure but later returned to the latter. I shall hereinafter call these cards the "Zener cards".) In the first use made of those there were 300 trials, and, although one subject got all five correct, the total hits were only 2 above np or chance. This is negligible. In the next series, 205 trials yielded only 35 as against 41 for np. This is 15% below chance expectation, the lowest percentage we have ever obtained in our regular experiments in a series of over 100 trials. This was, however, not significantly low at all, being only 1% times the p.e. The last series, 430 trials, yielded 82, when np was 86. This is within the p.e. itself.

TABLE II

Extra-Sensory Perception of the Clairvoyant Type
Class Experiments. Zener and Rhine.
(Autumn, 1931.)

These 1,600 trials were enough, we thought at the time, to show that there was no highly appreciable extra-sensory perception in those particular groups under those particular conditions. We turned then to another line of technique. Neither trance-telepathy nor class-clairvoyance had been impressive, though both had held out faint promises of evidence—if we went on long enough. We began scouting for special subjects by the quick and easy method of having friends, students,—anybody—call off the cards (Zener cards) in a shuffled pack placed facedown on the table before them. During the winter months I made a collection of these trial scores totalling 800, with 24 subjects, yielding 207 hits, with a positive deviation from chance expectation of 47. This deviation was our first really convincing result, since it was over 6 times the probable error and unquestionably significant. These results can be grasped most simply by many readers in terms of number of hits per 25 trials. These 800 trials averaged 6.5 in 25, while the chance average is 5 in 25.

These trials were all made in my presence, with fullest vigilance against deception, using cards that the subject had not had in his possession outside of my presence. Most of the subjects were friends or relatives or students from my classes. The subject usually looked at the back, sometimes picked the card up, but often did neither. He had no opportunity to learn the cards by marks on the backs, even supposing there to have been present a general visual hyperacuity. The chief advantage here over the tests given before was that when a subject did well he was encouraged to go on, when he did poorly he usually was not. This helped to guard the score somewhat by selecting the better scorers. For instance, I myself made only 15 calls in the 800, since I got only 2 correct in 15 trials. Mr. Mann has 105, because he got 37 correct in all, an average

TABLE III

Pure Clairvoyant Perception, Odd Tests, Winter 1931-32

Most of these figures cover more than one experimental occasion for the subject. We seldom ran over 20 trials per day, per subject. Mr. McLarty did; as did also Mr. Mann.

In order to avoid repeating description of conditions, I mention here the later results of the "Odds and Ends" that do not warrant individual presentation. Up to the end of the year 1932, there were 835 more odd trials at pure clairvoyance, yielding 208 successes, a gain of 41, which is 5.3 times the p.e.

Among this group were 100 trials by Dr. William McDougall, yielding chance average, 150 by Dr. D. K. Adams, also of our Department, giving 36 or an average of 6 per 25. Our greatest gain was the discovery of Cooper, who got 38 correct in 90 trials, a gain over np of 20, a deviation in itself 8 times the probable error. He has since done some most excellent work. For completeness, however, I must note that in these trials I did not myself supervise Cooper but asked another student, a friend of his, Mr. Harriman, to do it. Mr. Harriman, himself, got only 1 correct in 10, with the reverse arrangement. But if there were any doubt of Cooper's and Harriman's honesty, the further work of Cooper under supervision, reported in a later chapter, would adequately satisfy it.

We have, then, as a total of the odd clairvoyant tests 1,635 calls, yielding 415 successes, with a positive gain of 88, about 8 times the probable error. This is about an average of 6.2 hits per 25 trials. By these

) but he changed later on to the Zener cards. It is especially interesting to note that Stuart obtained better results than did Dr. Lundholm and I—not with the same subjects, it is true, and any comparison is based on all the uncertainties of individual differences. But it is easy to see now that Stuart, himself a student, working with fellow students who knew him well, did not induce the restraint and self-consciousness which Dr. Lundholm and I undoubtedly did with many student subjects. Stuart's results also warrant the detail of a tabular statement. (See Table IV). For a description of the technique of the three procedures used see the experiments of Dr. Lundholm and myself above. Instead of the circle-8 test Stuart used the 5-drawings test mentioned above. It will be noted that the best results were obtained with the 5-symbol cards and this has been pretty much the general case. The values of X or deviation divided by p.e. are, in order, 4.1, 2.3, and 5.5. When combined by taking the square root of the sum of their squares, we have 7.24. Combined with our last figure of accumulated value against "chance", 8.9, we get the mean square, 11.5, as our more advanced fortification against the chance theory.

TABLE IV

Trance-Telepathy Tests, Conducted by C. E. Stuart, Spring 1931

Table IV Stuart went over to the pure clairvoyance tests, using the Zener Cards. The procedure was essentially the same as that used by me in the exploratory tests for clairvoyance, except that Stuart used to shuffle the deck after each 5 cards, unless the calls were checked only after the entire 25 were called. I myself seldom did this, since few subjects tried to keep track of the cards already called off and checked, and seldom were all of a given symbol drawn. At worst, however, the probability would very occasionally be increased to % for the last 5 calls. It was, however, a point in favor of Stuart's caution. He, himself, in running did not look at the cards; he held them behind his back in his own calling. See Table V for the results up to the fall semester, 1931.

TABLE V

Pure Clairvoyance, by Stuart as observer, Spring and Summer, 1931

Name of Subject	No. of Trials	No. of Hits	Dev. from np.	Remarks
Scott	520	150	+46	Nearly 8 times the p.e.
Stuart	250	76	26	Unwitnessed; over 6 times p.e.
Mintier	100	26	6
D. Adams	85	29	12
Miller	45	15	6
Stiger	30	9	3
Whitehead	25	7	2
W. P.	20	2	-2
C. E. F.	15	3	0
Total	1,090	317	+99±8.9	X(D/p.e.) = 11.1

The last figure given for the combined value of the ratio of positive deviation to p.e. was 11.5. Stuart's results in Table V alone contribute a value for X of 11.1. Combining these, then, in the proper manner, we arrive at 16.1, a value that renders the alternate theory of "random distribution" or "chance" still more hopelessly unacceptable.

Mr. Harvey L. Frick, a graduate scholar in our Department, had in May, 1931, just completed his Master's thesis on the subject "Extra-Sensory Cognition", in which he presented evidence from telepathic and clairvoyant drawing-tests carried out with considerable distance between the agent and himself as percipient. He undertook, then, to do some pure clairvoyant work as well. He was interested in the decline curve suggested by the work of Richet, 1 Jephson, 2 and Estabrooks, 3 and decided to run 100 clairvoyant trials per day for a time, calling suits on playing cards, and then total the results in order of 20's in the hundred. That is, he added up the results by the various 20's for all the runs made. He totalled after 9 days and secured a very striking decline curve. This meant

Table VI. Frick's 3,120 trials in clairvoyant card-guessing, interesting though they are in their decline relationship, raise the ratio of positive deviation to p.e. only slightly, from 16.1 to 16.4.

TABLE VI

Clairvoyant Perception of Playing Cards, H. L. Frick, Spring, 1931
Total Deviation from (np) chance by order of 20's

Date	Total Trials	1st 20's	2nd 20's	3rd 20's	4th 20's	5th 20's	Remarks
5-15-31 to 5-24-31	900	+13 (±3.92)	+5	+3	-7	-9	+13 to -9 = 22±5.5 (p.e. d) X = 4.0
5-25-31 to 5-29-31	600	+12	+4	+7	-3	+7	+27±7.15; X = 3.8
Totals	1500	+25	+9	+10	-10	-2	+32±11.3; X = 2.8
5-29-31 to 10-13-31	1300	+1	-3	+9	+6	-3	+10 ±10.5; X = 1.0
Broken runs	320	7
Total	3120	+33	+6	+19	-4	-5	+49±16.3; X = 3.

In the spring of 1931 Miss Miriam Weckesser, my sister in-law, then 15 years old, found she could do clairvoyant perception, if left alone, but did not do above chance with the telepathic condition added. She was encouraged to work at it from time to time through the succeeding

TABLE VII

Lecrone's Experiment, Telepathy plus Clairvoyance, Summer, 1931

Condition	No. Trials	No. Hits	Avge. per 25	Deviation and p.e.	X, or D/p.e.
L. to A.A.P.	890	216	6.0	38 ± 8.0	4.7
A.A.P. to L.	820	176	5.35	12 ± 7.7	1.6
Total	1710	392	5.75	50 ± 11.2	4.5 (4.97 computed from √(4.7)2 + (1.6)2)

One more large group of data belongs in this miscellaneous collection, namely, that supervised during the year 1931-32 by Mr. J. G. Pratt, an assistant in the Department. Using the regular procedure already described for pure clairvoyance testing, with the Zener cards in packs of

Table VIII.

TABLE VIII

Clairvoyant Perception Tests, by Pratt as Observer, 1931-32

Name of Subject	No. of Trials	No. Correct	Deviation and p.e.	Value of X	Remarks
J. G. Pratt	2,885	634	+57 ±14.5	3.9	Investigator. Av. per 25 = 5.5
F. M. Pratt	1,975	403	+8 ±12.0	0.7
Robertson	1,150	245	+15 ± 9.1	1.6
Sapp	950	219	+29 ± 8.3	3.5
Miscellaneous	3,075	650	+35 ±15.0	2.3
Total	10,035	2,151	+144 ±27.0	5.3	Average per 25=5 4

There are no other large "batches" of data except those about to be reported in the chapters named for the subject producing them, with the following exceptions (This laborious explanation must be given since many will want to know if anything is omitted—especially of the lower scores): for a year and a half, now, we have followed the policy of giving a new subject a preliminary test, the results not to be taken into the record no matter what they are. When the subject gets 3 hits in 10 or better, the record can be started on the next trial following but must be so designated at the time. If, during the performance for record, the score drops below a 6 in 25, it is legitimate to quit scoring for the time. These preliminary test data have been rejected. My estimate of them, from memory and my own experience, is that they were on the whole above chance-average anyhow and probably represent only a few hundred trials with those subjects who later came into good scoring. But there have been a few subjects who have "practised" for thousands of trials without getting above the chance expectation (np). No conclusion of this report would be changed or appreciably weakened by including these practise data. For that matter, no amount of failing to score above chance by any number of other individuals can seriously affect our judgment of the results of those who succeed, since an individual ability is in question.

Table IX.

TABLE IX

Clairvoyant Perception; Odd Data, 1932-33

Period	Subject	No. of Trials	No. Correct	Deviation from np.	Remarks
Spring, ’33	Burling	450	120	+30	Unwitnessed.
Spring, ’33	H. Johnson	300	124	+64	Witnessed. Subject's eyes closed. 10 feet away.
Spring, ’33	J. Ellis	200	44	+4	Witnessed. Regular clairvoyant conditions.
1932	5-Word Test	70	16	+2
1932-33	J. B. Rhine	235	63	+16	Unwitnessed.
1932-33	L. E. Rhine	90	26	+8	Unwitnessed.
Totals		1,345	393	124±10	X = 12.4

Someone may be interested in the cumulative value of X for all the data (23,550 trials) reported in this chapter; it rises to 22.7, a value of indisputably great significance.

None of the data reported in this chapter is essential to any single point made in this report. On every score better results under better conditions are available. Why then, the labor and expense of publication—if, indeed, the answer is not obvious? To give the reader the opportunity to see the whole of the case, in its infancy as well as later, at its worst and most doubtful levels as well as at the more striking stages; and to reassure him that no important block of facts is omitted. Also, some of the weaknesses of these beginnings one has only to read here to avoid. They may help to guide those who will repeat these tests.

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Footnotes

54:1 Richet, Charles, La Suggestion Mentale et la Calcul des Probabilités, XVIII, 1884.

54:2 Jephson, Miss Ina, Evidence for Clairvoyance in Card-guessing, Proc. S.P.R. 38: pp. 223-271, 1928.

54:3 Estabrooks, G. H., A Contribution to Experimental Telepathy, B.S.P.R., Bulletin V, 1927.