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History and philosophy

Mesmerists, mediums and mind-readers

Peter Lamont with a brief history of extraordinary psychological feats, and their relevance for our concept of psychology and science.

18 April 2009

Derren Brown is a psychological illusionist. Far from attributing his ‘mind control’ feats to paranormal abilities, he expressly rejects the existence of paranormal phenomena, and has suggested (either explicitly or implicitly) that he relies upon techniques such as neurolinguistic programming and reading people’s body language. He is an intelligent and creative performer, and frames what he does in subtle and ingenious ways. However, when students ask whether his extraordinary abilities are real, I feel a need to remind them that he is an illusionist. Indeed, he, and a host of lesser mortals who have recently jumped on the psychological bandwagon, are the latest in a long line of mesmerists, mediums and mind-readers who demonstrated equally remarkable psychological feats, and who convinced many people that they were genuine. They gave their abilities different names, of course, and made their claims with various degrees of sincerity. Nevertheless, in the process, they managed to provoke all sorts of disagreement among key figures in the history of psychology about psychological processes, scientific expertise and disciplinary boundaries.

During the 1830s and 1840s, for example, mesmeric performers gave public exhibitions in which they placed their subjects into a coma, and demonstrated phreno-mesmerism and insensibility to pain. These public demonstrations would typically begin with a lecture on the scientific truth of mesmerism, then the mesmerist would pass their hands over the subject and declare that he or she was in a coma. In a demonstration of phreno-mesmerism, the mesmerist would touch or point to part of the skull (thus exciting a phrenological organ via the magnetic fluid), and the subject would then behave according to the relevant faculty. If, for example, it was the organ of Veneration, they might go down on their knees and hold their palms together as if praying. The power of such performances was that they appeared to demonstrate the truth of phrenology as well as mesmerism, providing the audience with direct observable evidence that distinct parts of the brain corresponded to different aspects of character. As John Elliotson, one of the key medical advocates of both phrenology and mesmerism noted at the time, ‘where formerly one had been converted to the truth of phrenology, now, through mesmerism, one hundred were converted’ (Cooter, 1984, p.150).

There were also countless demonstrations of insensibility to pain. One of the most successful early mesmeric performers, Lafontaine, fired a gun beside the ear of the subject in a theatrical display of insensibility, while others were subjected to bottles of ammonia being held under their noses by sceptical medical men. On one occasion a subject inadvertently demonstrated mesmeric analgesia when he was assaulted with a stick by a member of the audience.

In addition to drawing enthusiastic and often hostile audiences, these demonstrations became part of a much wider debate about the nature of mind, its relationship to the body, and scientific authority more generally. After all, at this time, reports that mesmerism was being used to facilitate painless surgery were being rejected by senior surgeons on the basis that one could not trust the testimony of patients. Following one well-known case of leg amputation, for example, Marshall Hall claimed that the lack of a reflex action showed the patient must have consciously suppressed the action. When the well-known writer, Harriet Martineau, claimed to have been cured by mesmerism, Benjamin Brodie (President of the Royal College of Surgeons) claimed that she was not qualified to know, while Charles Darwin thought she was hysterical, noting that a ‘tendency to deceive is characteristic of disordered females’ (Winter, 1998, p.226). The mesmeric performers were controversial not only because they demonstrated the analgesic properties of mesmerism but also because some of them facilitated painless tooth extractions and claimed they could cure a variety of ailments.

However, while they challenged medical authority, they also contributed to psychological theory. Thomas Laycock came up with the notion of reflex action in the brain, following a demonstration of mesmeric phenomena at University College Hospital; and James Braid first began to explore the psychological nature of mesmeric phenomena (which he later termed ‘hypnotism’) after witnessing a performance by Lafontaine. Braid, however, was sceptical about the so-called ‘higher’ phenomena of mesmerism, such as clairvoyance, which was being demonstrated by various subjects who seemed to be able to see whilst blindfolded. Braid even suggested how they could peek from behind the blindfold, and others conducted tests that suggested this was indeed the source of their clairvoyant abilities (Lamont, 2008). Nevertheless, similarly remarkable feats soon took a different form, and provoked alternative psychological explanations.

By mid-century, modern spiritualism had arrived, and the spirits seemed to be able to read minds and move tables. In an attempt to explain table movements by natural means, the eminent psycho-physiologist, W. B. Carpenter, came up with the theory of ideo-motor action, suggesting that sitters, whose hands were in contact with the table, were unconsciously pushing it. The philosopher of mind George Lewes wrote a satirical piece describing how the medium relied upon reading body language to gain information from the sitters, and explained how he had surreptitiously used this to mislead the spirits into communicating that the medium was an impostor.

Nevertheless, many of the reported phenomena remained unexplained. When the most famous medium of the time, Daniel Dunglas Home, was tested in 1870, he convinced his experimenters that he was in possession of a previously unknown ‘psychic’ force. This prompted Francis Galton to observe further tests with Home, which he described to Darwin as ‘thoroughly scientific’, and to encourage his cousin to get involved. One of those present at the original experiments, Edward Cox, the man who first coined the term ‘psychic’, went on to found the Psychological Society of Great Britain in 1875 (pre-dating the BPS by quarter of a century: see Lamont, 2004; Richards, 2001).

In Germany, the two great fathers of scientific psychology Gustav Fechner and Wilhelm Wundt attended séances with the notorious medium Henry Slade. Fechner, according to a colleague, was convinced that what he saw was real (though he himself later denied this). Wundt, on the other hand, was convinced that Slade was a fake (though he was unable to explain how it was done). Nevertheless, Wundt wrote a long and scathing article in which he denounced Slade as a fraud and those scientists who thought otherwise as incompetent. This was in 1879, just a few months before he established his famous research laboratory in Leipzig (Marshall & Wendt, 1980). In the United States, the medium Mrs Piper managed to baffle all who tried to discover how she might have been cheating. William James described her as his ‘white crow’, as it only took one genuine medium to show that not all mediums were fraudulent. Other eminent psychologists, such as G.S. Hall, Hugo Munsterberg and Joseph Jastrow, went out of their way to debunk mediums in a bid to show that psychological rather than psychic processes were behind these seemingly inexplicable phenomena (Coon, 1992).

With the emergence of the late Victorian ‘thought-readers’, such as Washington Irving Bishop, performers began to employ muscle-reading to discover where a member of the audience had hidden a small object (by holding the wrist of the person and having them think of the location, then picking up on subtle physiological cues as to where it was hidden). Bishop impressed Carpenter with a card trick that the latter found to be ‘of great psychological interest’, but which almost certainly relied on a much simpler method. He was tested by the pioneer of comparative psychology George Romanes, along with Galton and George Croom Robertson (editor of Mind), who were less impressed. In the report in Nature, they criticised Carpenter for having recommended Bishop to the attention of science (Luckhurst, 2002).

Such feats were, however, worthy of the attention of psychology. If true, mesmeric, mediumistic and mind-reading feats had significant implications for psychology. Even if such feats did not involve any extraordinary abilities, it is clear that the most ardent of sceptics often did not know themselves what was going on. Thus, though few psychologists were actively involved in psychical research, both proponents and critics, from Freud to Binet, felt that it contributed to our understanding of psychological phenomena.

For some psychologists, the public demonstrations were a problem because they confused the boundaries between science and pseudo-science, and challenged scientific authority on psychological matters. Thus, they sought to debunk psychical research as unscientific, and to provide psychological explanations for belief in such phenomena. Carpenter wrote a series of articles on the psychology of deception and self-deception, in which he discussed the problems of testimony and the psychology of belief. Jastrow later wrote several papers on the psychology of deception and on the pseudo-scientific nature of spiritualism, and both wrote about the psychology of conjuring (a topic also studied by Binet and the pioneering social psychologist Norman Triplett). Alas, their expertise was not always adequate, and some of their debunking attempts were themselves the result of ignorance, gullibility and wishful thinking (Lamont, 2006). Furthermore, the question of who was the appropriate authority on such a topic continued to be a matter of dispute. In 1924, for example, when the medium ‘Margery’ was investigated by William McDougall (then Professor of Psychology at Harvard), it led to his having a public argument with Houdini about who was better qualified to assess her (Kalush & Sloman, 2007).

Those who demonstrated extraordinary psychological feats are still relevant today, because key historical and conceptual issues in psychology remain concerning the scope and status of psychological knowledge and its relationship to society. In the absence of any agreed criteria that neatly distinguish between science and non-science, and given psychology’s disputed scientific status, the authority of psychological knowledge rests upon an ability to argue that it is superior to lay thinking about mind and behaviour. While the nature and scope of psychology may have changed over time, this central argument has not (indeed, it has often been the underlying reason for disputes over what psychology should be). It is through these disputes that we have determined what counts as valid psychological knowledge. The arguments provoked by the mesmerists, mediums and mind-readers of the past, like the psychological illusionists of today, remind us that what counts as psychological reality is neither self-evident nor universally accepted.

-    Peter Lamont is Programme Director of the MSc in History and Theory of Psychology, University of Edinburgh; he is also a former President of the Edinburgh Magic Circle
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