Extra-Sensory Perception, by J. B. Rhine, [1934], at sacred-texts.com
My acquaintance with the author of this book dates from 1926. I early learned that he was keen to discover the indicia of deception within the field of psychic research, and at the same time, while open-minded, only to be convinced of any of its claims by a slow process of evidence and sound reasoning. My estimate of the qualifications of an ideal psychic researcher is very exacting, and already in that year, before I had any idea that he would find opportunity as a psychologist to devote much attention to psychic research, I earnestly wished that he might be able and inclined to do so.
The momentous study here presented has what may be called, metaphorically, three dimensions. First, there is the unprecedently long period, about three years, during which experiments have been conducted until they reached a vast number. Secondly, we find that the co-operation, observation, and critical judgment of many persons both within and without the teaching staff of the psychological department of Duke University have been applied to the experiments at various stages. Thirdly, we note the waxing rigor of the main stream of the experimentation, and the diversity of methods employed not simply to pile up proof to astronomical proportions, but to isolate telepathy and clairvoyance, each from the other, to find out what measures enhanced and what detracted from results, and to acquire data to test this and that hypothesis of the processes involved. Many admirable series of experiments for extrasensory perception have been made by men of science and other men of university education and high mental endowment, especially since 1880, with some of earlier date. But in none of the particulars stated above can any of them compare with the great task accomplished at Duke University.
To be sure, some of the series of trials reported in this book rest, prima facie, upon the good faith of unwitnessed experimenters. The author could well have afforded to omit all of these, for the host of experiments witnessed under rigid conditions are enormously sufficient to bring the odds against chance to tremendous figures. But he wished to tell the whole story. Pearce's 15,000 witnessed trials under diversified conditions alone would have been abundantly ample upon which to rest the case as regards proof. But it is certainly worth while to know if some subjects can get results better when alone and others can not and how the general progress under the two conditions compares. Besides, our
confidence in the reported unwitnessed results in some cases is established by finding that their subjects did as well or better under inspection. And it is hard to discredit those persons whose unwitnessed results declined against natural wish or displayed under analysis, as will be shown, striking analogies, which could not have been foreseen by the subjects, with results received under inspection. But let the reader discard all these which he will, there remains a huge block of evidence against which it would appear that skepticism must batter in vain.
"Unconscious whispering" has had a larger place in psychical research discussion than it ever deserved, but in this report conditions under which, even though near the agent, the percipient could not have heard any such, and separation in different rooms and buildings, have banished this ghost. The discovery that some of the subjects did better at considerable distances is a noteworthy one. Some other writers have reported the reverse, but it may be that their subjects were too abruptly removed to a distance or that some other factor caused them to lose confidence.
This report agrees with most others in the effects of mental comfort, calm, and abstraction in promoting success. But here much experimentation was done, expressly to measure the effects of various disturbances. So far as subjects were ill, their scores fell. But why should anyone not guess (that is, with all sensory data for judgment excluded) as well when ill as when well? Success declined when the percipient against his own desire was kept at the task until it was highly distasteful. But why should pure guessing be thus put at a disadvantage? At first, when conditions were suddenly changed as by the interception of a screen, scoring would fall, later to rise, and so also when a visitor was brought in while a series was in operation. A certain drug markedly and consistently lowered the ratio of "hits," another drug tended to restore the ratio. There is no conceivable way by which pure guessing could thus be affected. There appears to be no explanation save that the various disturbances, including the administering of a certain drug, unfavorably affected that mental state most productive of extra-sensory perception, and that another drug mysteriously affected that state favorably.
The results of a single experiment may have great evidential force. Such an experiment has been lately reported by Mr. Theodore Besterman, a very careful and conservative researcher. 1 The subject was Ossowiecki, with whom Dr. E. J. Dingwall, an experienced investigator whose bent is toward skepticism, several years ago had a result almost equally amazing. Mr. Besterman employed precautions the avoidance of which baffles the mind to imagine. The odds against chance in his case cannot be mathematically evaluated, but it is safe to say, after considering all the factors involved, that they could not be less than a million to one.
Nevertheless, probably many a scientific man, in spite of the critical character of the reporter, the precautions described, etc., will think there was some hocus-pocus in this case. But how can he suppose that a group of intelligent men, some of them belonging to a University staff, could, through a period of three years, all the while intent on sure conditions, where such conditions were so easy to devise and apply and where the described precautions were so multiplied and diversified, be all the time fooled by each other? Learned men have been obfuscated by tricks played in dark seances, with various crippling conditions prescribed by the medium. But the Duke University work was done in the light with all conditions under command of the experimenters. If the reader will peruse carefully, he will find that any explanatory suggestion which his imagination can furnish regarding a particular series of tests is effectually demolished by the conditions of many another series.
It is indeed extraordinary that so many good subjects were discovered. I am inclined to attribute this to three main factors; (1) the general harmony amid which the work was done from the first, the perhaps unprecedented fact that the President of the University, the entire teaching staff of the psychological department from Dr. McDougall down, and other experimenters were open-minded and sympathetic to the unusual experimentation; (2) the tactful methods of approaching and dealing with subjects, maintained by Professor Rhine and shared by others; (3) the gradual selection and segregation of hopeful subjects, and supreme patience in the continuance of tests with these.
Perhaps, in addition to Rhine's control experiments on the mathematics of probability, a specimen exhibit of what mere guessing can do will be worth while. I started out with the idea of discovering clairvoyant ability in my own office. After a number of non-significant experiments with another person, I set out to test Pure Clairvoyance on myself alone with one set of Zener cards, shuffled after every five trials, and unseen. After one thousand, I had made 209 hits, an excess of only 9 above mean expectation, quite insignificant in so large a number of trials. My second thousand, done in the same way, yielded 201 hits, but 1 in excess of mean expectation. The first 500 of a third thousand was done in the same way, but, since nothing but chance seemed to be in operation, I then employed a device which guaranteed chance only, and the third thousand showed 199 hits, or 1 below mean expectation. The fourth thousand, with guaranteed chance results, resulted in 193 hits, or 7 below. It might now seem as though there had been a very slight clairvoyance in the first two sets, so I went through a fifth thousand, again by the method allowing clairvoyance to enter, through some hundreds working slowly, through others more swiftly, neither method showing an advantage. But my hits for
this thousand were fewest of all, being 188, or 12 below. And the total for five thousand trials was 990, a deviation from mean chance expectation (below) of but 10, which for so large a number is quite insignificant of anything but chance.
There were, of course, groups in the course of the experiments where scores shot up, and other groups where they rapidly dropped, but in the course of a thousand, these vagaries, so to speak, nearly ironed out. Taking the hundreds consecutively, twice I made as many "hits" as 35 in a hundred and once as few as 9. In the first thousand, five sets (that is, of the 5 cards) were guessed with entire accuracy, in the second none were, though both were done by the P.C. method. In each of the third and fourth thousands, I got one 5-card set entirely right, and in the fifth, two sets. Were there gleams of clairvoyance in the first thousand particularly? Possibly, but probably we have only high points of chance, which must be expected. At any rate, we have in five thousand a deviation of 10 from mean expectation, indicative of chance only.
Contrast these results with those of Dr. Rhine's selected percipients! Even though there should come criticism of any results obtained by a higher order of mathematics announcing successively the mounting values of X, it would amount in the end merely to the exchange of one astronomical figure for another. The mere statistics in many tables giving the average number of successes per 25 through various long runs of trials, and not less the statistics of effects produced by various species of purposed disturbances and of recovery therefrom, given in the same terms of number of successes per 25, would seem to make the notion of chance entirely out of question.
While the chapters of this treatise are in proper logical sequence, I am tempted to suggest that some lay readers might, before reading the book as a whole, acquire a taste for its contents by first reading certain selected portions. Let them place a book-mark for reference at page xiv in order that they may at any point consult the table for the meaning of abbreviations. Also, as one will find frequent evaluations of a series, or of total results to a date, in terms of "X" (an arbitrary sign equivalent to "D/p.e.") which signifies the odds against chance, I advise him (unless he is a mathematician) to keep a book-mark at page 32, so that when he finds the statement that X is 13 or 20 or 30 or a higher figure he can turn to that page and seeing that in the progress of X from 1 to only 9, it has already reached an anti-chance valuation of more than 100,000,000 to 1, he can better understand what the statement implies. Mathematicians think it rather silly to demand to know exactly the valuation of X 15, etc., for if one is not satisfied with odds of a hundred million by what would he be satisfied? Then let pages 109-113 be read, and then Chapter VII, describing the nature and analyzing the results of Pearce's great number
of 15,000 witnessed experiments. By this time, if not before, the reader should have acquired zest to carry him through the whole book, from the first to the last word.
Comments, questions, and criticism from any readers, and especially such as are of scientific standing, are welcome, and may be addressed either to the author at Duke University, Durham, North Carolina, or to the Boston Society for Psychic Research.
x:1 Proc. S. P. R., Part 132, 1933.