Brian Clegg. Extra Sensory: The Science and Pseudoscience of Telepathy and Other Powers of the Mind. St Martins Press, 2013.

It probably takes some guts for an established science writer to write a book about ESP and the like, and not to immediately write the whole thing off without a moment’s thought. Perhaps being an outsider to the academic establishment Clegg is freer in such regard.
Clegg provides a critical but not unsympathetic account of the subject. His interest seems to have been stimulated by a teenage incident in which he felt he was in telepathic contact with a friend, and, I suspect, a more cautious approach developed when he had an extraordinary non-precognitive experience, awaking one morning with the absolute certain 'knowledge' that the plane he was going to fly on that day was going to crash. So powerful was this feeling that he persuaded his sympathetic boss to allow him to change flights. The plane did not crash, and nothing bad happened at all. Of course, if the plane had crashed, that would have been excellent evidence for precognition, or would it have just been a coincidence. Clegg points out that feelings like this which don’t pan out get forgotten, where those when some coincidence takes place become highly memorable.
He begins his exploration of telepathy by examining the possible theories advanced for it, or at least some of them. His main interest, as a (ex)physicist is Brian Josephson's linking telepathy with quantum entanglement, an idea towards which Clegg is not wholly unsympathetic, though this is a controversial idea even among paranormalists with a physics background. There are two reasons for that, one is that it is considered axiomatic that quantum entanglement cannot be used to break special relativity by sending messages, and by the feeling that the brain is a far too complex and messy environment for quantum effects to play much role. He is far more sceptical of other theories, involving electromagnetism or an, as yet unknown, new force. He also points out that dualistic views also have overwhelming problems.
Clegg argues that the main problem that scientists face in the field of parapsychology is that of cheating, and that this is especially the case in things like mediumship. I note that he came to the same conclusions as me over the Scole Affair, (he didn’t read my review, I checked the references!), pointing out how every attempt to introduce controls led to one evasion and excuse after another.
He examines in general some of the evidence for telepathy, precognition and psychokinesis, and points out some of the pitfalls in experiments such as those using the ganzfield, and also looks at the some of the work of Daryl Bem. He argues that in almost all of these studies, it is not clear that what is being studied is what the ordinary person would think of as telepathy etc, it is just statistical anomalies, which might suggest there is something there, but gives no clue as to what it is. He further notes that if PK is a real effect, affecting a moving dice would be a much more difficult feat than moving a very light static target.
He takes a detailed look at the original experiments of J. B. Rhine the work of the remote viewers and the tricks of Uri Geller, showing how they each had multiple methodological flaws. Parapsychologists might correctly point out that this really is a selection of weak cases, sceptics might reply that are cases that easily show up the methodological errors that occur more subtly in other cases. I would like to have seen some discussion of the complex debates between Charles Honorton and Ray Hyman here, though I understand that they be just too recondite for a popular readership. Clegg also examines the work of Dean Radin and PEAR (Princton Engineering Anomalies research) and I get the feeling that he really doesn’t understand what is being claimed here. Join the club!
Clegg is surely right when he argues that the endless debates about statistical anomalies will never get anywhere, what is needed are clear decisive experiments, which replicate real life more. Here’s a couple of examples of mine, for telepathy use identical twins in separate buildings, experiments performed by students who not told what the experiment is for, and monitor the brain activity of each. One twin is shown a series of slides of scenes ranging from the positive to the negative, from the arousing to the soporific etc. Experiments like these could be tweaked in a variety of ways. For psychokinesis, try moving a microgram weight in a completely environmentally controlled container (or given the claims that are made for RSPK) transmitting a microgram weight through a micrometre thick partition from one hermetically sealed container to another. To test what lies behind the statistical anomalies use computers doing millions of runs and not people.
Clegg suggests that parapsychologists do not look for final definitive experiments, because just going from one vaguely suggestive result to another is a way of keeping the subject going and maintaining their positions. [Much like ufologists, then – Ed.]
Perhaps they suspect that the answer to such a definitive experiment would be negative, and indeed sceptics can point out that there have been any number of real world experiments with negative outcomes, not one case of a completely unambiguous prediction of a truly unexpected event made before the event, no football referee spontaneously combusted. If psychic powers are real they ought to be as an obvious and public as outstanding athletic, musical, artistic or any other ability and to be a quotidian part of our lives not occasional anomalies. - Peter Rogerson


  1. Thanks for your thoughtful review. I would just point out that there is no problem with using entanglement as part of a process to send information - this is done, for instance, in quantum teleportation - the problem comes if you try to use entanglement to send information faster than light, which seems impossible to do, even though the entangled particles do effectively communicate instantly.

  2. Anonymous2.9.13

    I've always understood that the problem with using quantum entanglement as an explanation for telepathy is that the "information" transmitted can indeed apparently travel faster than light, but it isn't actually "information" in the usual sense. If you measure particle A and find it to have a particular spin, then particle B must have the opposite spin, even though it had no clearly defined spin at all until its sister particle was measured, and this must happen instantly, even if that seems to exceed the speed of light - in technical terms, the entire waveform collapses simultaneously, no matter how far apart its constituent particles are. But since the result of measuring particle A is completely random, this method cannot be used as, say, a way of transmitting instant messages in morse code over interstellar distances - all you can send is totally meaningless noise. Which isn't very useful. Even if the human brain can somehow transmit entangled quantum particles to other human brains in some as yet undetectable way (which isn't all that likely, to put it mildly!), there doesn't seem to be any way around this problem, even theoretically.

    As Albert Einstein pointed out when politely refusing to write a foreword for J. B. Rhine's pioneering book on ESP, a mysterious force detectable only through its results which does not diminish with distance, or indeed time (and can move backwards and forwards through time as it pleases), sounds one heck of a lot more like an experimental error than an actual thing. Especially if it's incredibly small, and sometimes disappears entirely for reasons as contrived as somebody in the room not having sufficient faith that the experiment will work!

    It should be added that, since ESP apparently has unlimited range without losing strength, the fact that I am actively doubting the existence of Psi as I type this logically ought to negatively influence the outcome of any ESP experiment going on right now anywhere in the world. And actually, since my quantum-entangled bad vibes can also travel through time in both directions without getting any weaker, I'm also putting the kibosh on any ESP experiment that has ever been conducted or ever will be! Can anybody explain to me why, if what currently passes for "Psi Theory" is correct, what I've just said is wrong?

    Really, the most interesting possibility seems to be that, just as medieval dowsers thought that because they found water exactly where their twitching twig said it should be, they had magical powers, whereas they were merely digging down at random and automatically reaching a water table that they didn't know about, these tiny results, assuming them to be genuine, prove that every seemingly random process in the Universe is ever so slightly non-random. The implications of this would be absolutely immense! Certainly a lot bigger than the claim, even if it's true, that some people can influence the results of a great many dice-rolls to a barely detectable degree, except for some reason when this would allow them to do anything the least bit useful, such as winning money in casinos.