GRAHAM WAGSTAFF is a psychologist at Liverpool University who has been studying hypnosis for 20 years. Ask him whether stage hypnotists should be banned and he answers with a clear "No".
It is not that he is a fan. He just doesn't believe that there is any such thing as hypnotism.
Neither does The Amazing Kreskin. He began a stage career as a magician and hypnotist when he was 11. Now 59, he still treads the boards in the US, but insists: "Nobody on stage has ever been hypnotised in the history of the world."
So certain is he of this he has offered a $100,000 reward to anyone who can prove that hypnosis exists.
Last week, after a series of complaints that people have suffered psychological damage as a result of taking part in stage performances, the Government decided to act. After revelations that one 24-year-old woman had died within five hours of undergoing hypnosis and a young man was said to have regressed to a mental age of eight, the Government agreed to review the 1952 law on public hypnotism.
When the Home Office review team gets down to work, it will have to reckon with the views of Dr Wagstaff, Mr Kreskin and other sceptics, who insist that stage hypnosis is not a question of meddling in people's subconscious but is more a question of audience credulity.
It was a similar series of cases and allegations about mind control that first prompted an attempt to regulate the controversial world of hypnotism: the 1952 Act requires stage performances to be licensed by local authorities.
But the debate began back in the 1770s, when a Viennese physician, Anton Mesmer, evolved a system of medical treatment based on "animal magnetism'', a theory that the human mind and body respond to magnetic forces.
Not long afterwards a French aristocrat, the Marquis of Puysegur, identified the phenomenon he called "magnetic sleep", or the hypnotic trance, and began using it in therapy.
Establishment physicians dismissed this as mountebank science, and it has gained acceptance only in the past 100 years with the evolution of psychology and psychiatry. Today it is widely used in psychotherapy, but even those experts who believe in it accept that most of what goes on during performances of stage hypnotism is a form of exhibitionism.
According to Michael Heap, lecturer in clinical hypnotism at Sheffield University, sceptics such as Dr Wagstaff have a problem in explaining the experiences of those undergoing true hypnotism. People who have been told under hypnosis that they will not feel pain insist that they do not.
Dr Heap also cited research by Karen Olness at the University of Minnesota, in which children had successfully increased the concentration of a particular antibody, immunoglobulin A, in their saliva following hypnotic suggestion.
There were other studies, he said, showing that if hypnotised subjects were told that their hand was getting hot, the measured temperature of the hand would indeed rise.
Dr Wagstaff, however, insists: "The whole concept is a fantasy, a cultural invention." He says that people want to believe that some simple route exists to the troubled, hidden corners of their mind.
That, and the desire to show off, according to Dr Wagstaff, is what drives people to take part in stage hypnosis, and from the moment they reach the stage they are led on by the pressure of the situation and the power of suggestion.
He also disputes the veracity of hypnosis used for pain control, arguing that endurance of suffering is due to a high pain threshold of an individual patient rather than hypnosis.
Dr Wagstaff, like scientists in the US and Canada, has conducted studies comparing the behaviour of people who have been hypnotised with that of people who have not. If both groups were given similar instructions, he found no significant difference in their responses.
People under hypnosis, he argues, behave oddly because they want to believe in it and because they are willing to comply with suggestions made to them. But why are they prepared to make themselves look ridiculous?
"They don't have to be hypnotised to do that. Look at what they are prepared to do on television for Bruce Forsyth or Noel Edmonds," says Dr Wagstaff.
Mr Kreskin lost his belief in hypnosis about 20 years ago, when he was called in to help a psychologist treat his patients. They found that patients for whom hypnotic techniques clearly did not work were just as likely to recover as those for whom they did.
Mr Kreskin now devotes his act to debunking hypnotism.
"I have shown that everything that we associate with hypnotism can be done without any voodoo-like induction," he says.
"If people are persuaded and motivated they will do any of these things."
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