Richard Wiseman and Ganzfeld Telepathy Research


Richard Wiseman and Ganzfeld Telepathy Research


The Wiseman & Milton Controversy

by the Editors


On Richard Wiseman’s “obvious self-interest”.

Since the 1970s one of the most popular kinds of telepathy experiment among parapsychologists has been the ganzfeld procedure.

The German word “ganzfeld” means “whole field”. In these experiments subjects are placed in conditions of mild sensory deprivation, sitting in a comfortable reclining chair, listening to white noise played through headphones, and wearing translucent hemispheres over the eyes – halved ping-pong balls – while red light shines on the face. Meanwhile, a “sender” in another room looks at photos or video clips, and the subject speaks about any feelings or images that come to mind. At the end of the session the subject is shown four different stimuli, only one of which was shown to the “sender”, and ranks them. There is a 1 in 4 or 25% chance of scoring a hit by chance, by ranking the actual image first.

In many such trials subjects have scored very significantly above chance levels, and several meta-analyses have shown a very significant overall effect. In 1999, Richard Wiseman and his colleague Julie Milton published a meta-analysis in Psychological Bulletin that they claimed shown no overall significant effect, and publicized their findings widely in the media, claiming that ESP did not exist.

This skeptical claim generated a great deal of controversy in technical scientific journals, because most of their colleagues considered their analysis to be biased and seriously flawed, both in the methods they had used, and in the way they had selected the data. In particular, they had chosen to omit some recent and highly successful experiments. Milton (1999) later admitted that when these data were included in the analysis, the results were indeed positive and statistically significant.

Nancy L. Zingrone, Ph.D., then the President of the Parapsychological Association, the professional society to which Wiseman and Milton criticized Wiseman for “obvious self-interest”. In a letter to the Journal of Parapsychology, he objected that she had not supported her criticism with appropriate references, and she replied as follows (in The Journal of Parapsychology (2002), 66 (2), 212-216):

The Milton and Wiseman meta-analysis … sparked controversy to some extent because it seems to have been conducted and published more from self-interest than from a sincere wish to test the hypothesis at hand…. In response to his letter, I have returned to my database and discovered that I did not, in fact, cite all the criticism and response available. Therefore, taking his comment into account and keeping to my intention of not allowing heavily criticized work to be cited without qualification, I would like to amend my reference citation to the following:

(See Milton & Wiseman, 1999. For criticism see Bem, Palmer & Broughton, 2001; Errata, 2001; Schmeidler & Edge, 1999, pp. 335-360; Storm, 2000 & Ertel, 2001; and Storm & Thalbourne, 2000, pp. 298-299. For response to criticism see Milton, 1999; Milton & Wiseman, 2001; and Schmeidler & Edge 1999, pp 335-360).

I would also like to qualify the use of the word “obvious” in reference to the self-interest that, in my opinion, seems to underlie the Milton and Wiseman meta-analysis. What is “obvious” to me may only be apparent to other readers of the published literature. The context in which I have read the published record of this controversy may be different from other readers because: I had read a draft of the paper before it was published in Psychological Bulletin; I was present at the 1997 PA Convention where a previous version of the Psychological Bulletin paper was presented; I have had other critical contact with other writings of Milton and Wiseman in normal scientific interactions (such as participating in the peer review process); and I have analysed other writings of Dr. Wiseman for my thesis research which focuses on criticism and response. Finally, I have also been present on email chat lists in which Dr. Wiseman’s work in general and the Milton and Wiseman meta-analysis in particular have been discussed. My opinion arises from that context and as such what is obvious to me may only be apparent or a faint suspicion to others. Of course, there must also be those who would disagree with my position, having formed an equally strong but opposite opinion.

There are also, however, some specific characteristics of the Milton and Wiseman meta-analysis and the way in which they present and defend it (Milton, 1999; Milton & Wiseman, 1999; Milton & Wiseman 2001) that signal to me rather than asking the underlying scientific question – is the ganzfeld still a useful method of parapsychological research?-Milton and Wiseman were gathering evidence to support an a priori commitment to the notion that all positive psi results are spurious and all methods which seem to show the presence of psi are flawed. I realize I am also making a very strong claim. I am aware that I could be in error. But I provide here some published evidence to support my points.

The first is the following. Milton and Wiseman seemed to have missed an obvious opportunity for peer review in their rush to publish their 1999 Psychological Bulletin paper “Does Psi Exist? Lack of Replication of an Anomalous Process of Information Transfer.” It is usual in the parapsychological community for people to “try out” papers that will eventually be published by presenting them at the annual Parapsychological Association conventions. An extra layer of pre-publication protection from errors of fact or method is provided to authors first by the convention refereeing process and, second, by the experience of presenting at the convention and fielding questions and criticisms both on the convention floor and in informal encounters. It seemed to me to be odd at the time that Milton and Wiseman chose to submit their convention version to Psychological Bulletin after it had been accepted for the Proceedings of Presented Papers but before the actual presentation at the convention. That is, they submitted “Does Psi Exist?” to the Psychological Bulletin slightly more than six weeks prior to the PA Convention. The submission was received by Psychological Bulletin on June 23rd, 1997 (Milton & Wiseman, 1999, p.391), and the convention took place from August 7th – 10th, 1997.

One wonders why Milton and Wiseman made the decision to forego the opportunity for more detailed critique which could reasonably have been expected to be available at the convention just over six weeks later. It seems to me that it would have been in the best interest of science to wait to revise the paper until after they had heard and considered the criticisms raised by their colleagues on the convention floor. Their decision seems especially unfortunately given the number of errors in their original work that they have since been identified in print. These errors have included statistical problems in the original meta-analysis (Schmeidler & Edge, 1999, pp. 340-349; Storm, 2000, pp. 411-413; Storm & Ertel, 2001, pp 425, 427, 429-430; Bem, Palmer & Broughton, 2001, pp. 208-209); procedural problems in coding, blocking, and inclusion criteria (Schmeidler & Edge, 1999, pp. 336-339, 349-360); and a miscalculation in the original study table (Milton & Wiseman, 1999, p. 388) that was used in a later meta-analysis (Bem, Palmer & Broughton, 2001, p. 210) and then corrected by the editors of the Journal of Parapsychology (Errata, 2001, p. 428).

Dr. Wiseman would probably argue that he and his colleague, Dr. Julie Milton, have answered all the criticism adequately (Milton, 1999; Schmeidler & Edge, 1999; pp. 349, 353, 354, 358, 360; Milton & Wiseman, 2001) but the fact that the controversy re-erupts on a regular basis shows that closure has by no means been reached. That is, Milton and Wiseman have not convinced their critics that their procedural and analytical decisions were correct nor have they convinced their critics that their conclusions were warranted.

The second is the following. There is a rhetorical problem with the way in which Milton & Wiseman have made very strong claims for the conclusions they reached in their meta-analysis. For example, in the original Psychological Bulletin paper, they stated in the abstract “The authors conclude that the ganzfeld technique does not at present offer a replicable method for producing ESP in the laboratory” (Milton & Wiseman, 1999. p. 387). This particular statement rests on their assumption that the effect obtained in the original Bem and Honorton paper had not been replicated in their own database (a conclusion disputed by several of their critics).

Based on their meta-analysis then, Milton and Wiseman have claimed in effect, that the ganzfeld research program was a waste of time and resources. This is a very strong claim that is, as the criticisms have shown, supported by a heavily-flawed meta-analysis (and I have barely skimmed the surface of the published criticisms that have been made in this letter). Yet in the face of these criticisms, Milton and Wiseman have continued to issue their strong claim both in Milton’s (1999) discussion paper and in their reply (Milton & Wiseman, 2001) to Storm and Ertel (2001), where they chide Storm and Ertel for inattention to the many identified flaws of the ganzfeld database. The only reason I can propose to explain why Milton and Wiseman steadfastly deflect criticism of their own work, presenting it as unproblematic and unflawed, is that they are unshakeably convinced of their conclusion and may well have been convinced of it long before they even began their work.

Of course, I may be in error, but that is the opinion I have formed. It is possible that I have assessed the magnitude and depth of the criticism incorrectly, but to be frank, I do not think that is the case. Whether I am correct or incorrect however, does not remove the fact that Milton and Wiseman have continued to ignore the controversy that has surrounded their meta-analysis. One can only hope that in future citations of their own work, they will show the same attention to flaws and criticisms they show when they cite the work of others.


BEM, D.J., PALMER, J., & BROUGHTON, R.S. (2001). Updating the Ganzfeld database: A victim of its own success? Journal of Parapsychology, 65, 207-218.

ERRATA (2001). Journal of Parapsychology, 65, 427-428.

MILTON, J. (1999). Should Ganzfeld research continue to be crucial in the search for a replicable psi effect? Park 1. Discussion paper and introduction to an electronic mail discussion. Journal of Parapsychology, 63, 309-335.

MILTON, J., & WISEMAN, R. (1999). Does psi exist? Lack of replication of an anomalous process of information transfer. Psychological Bulletin, 125, 378-391.

MILTON, J., & WISEMAN, R. (2001). Does psi exist? Reply to Storm and Ertel (2001) Psychological Bulletin, 127, 434-438.

SCHMEIDLER, G. R., & EDGE, H. (1999). Should Ganzfeld research continue to be crucial in the search for a replicable psi effect? Part II Edited Ganzfeld debate. Journal of Parapsychology, 63, 335-388.

STORM, L. (2000). Research note: Replicable evidence of psi: A revision of Milton’s (1999) meta-analysis of the Ganzfeld databases. Journal of Parapsychology, 64, 411-416.

STORM, L., & ERTEL, S. (2001). Does psi exist? Comments on Milton and Wiseman’s (1999) meta-analysis of Ganzfeld research. Parapsychology Bulletin, 127, 424-433.

STORM, L., & THALBOURNE, M.A. (2000). A paradigm shift away from the ESP-PK dichotomy: The theory of psychopraxia. Journal of Parapsychology, 64, 279-300.

ZINGRONE, N.L. (2002). Controversy and the problems of parapsychology. Journal of Parapsychology, 66, 3-30.

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