A Nobel prizewinning scientist has clashed with one of Britain's leading experts on the paranormal in a row over the purported talents of a Russian schoolgirl who claims she uses X-ray vision to diagnose medical problems.
Brian Josephson, a Cambridge University professor who won the Nobel Prize for Physics in 1973, has given his backing to claims by Natasha Demkina that she can see inside people's bodies.
The professor, who has been scorned by colleagues for his enthusiasm for the paranormal, has claimed that an experiment for a forthcoming terrestrial TV documentary that apparently disproves Ms Demkina's claims was "a fix" designed to ensure she failed.
Richard Wiseman, professor of psychology at Hertfordshire University and a key member of the respected Committee for the Scientific Investigation of Claims of the Paranormal, who helped design the experiment, hit back this week.
He said that the attack from Professor Josephson, who is a physicist with no known record of publishing on parapsychology, "does not carry much weight", as it was posted on his personal website without any refereeing process.
But he admitted that the trial could have been improved.
The experiment to test Ms Demkina's claims was filmed for a Discovery Channel documentary, The Girl with the X-ray Eyes , which is also due to appear on Channel 4 next year.
In the programme, Ms Demkina correctly identifies the medical conditions of four out of seven patients, and misdiagnoses three.
Professor Josephson says, on his Cambridge University-hosted website, that "many viewers ended up with a strong impression that the test... had been deliberately set up with a view to ensuring that she would fail it".
He says that, in difficult circumstances, Ms Demkina overcame odds of more than 50 to one to correctly diagnose four patients.
"Surely a case for celebrating Natasha's success?" he says.
But instead, it was declared that Ms Demkina had failed the test as the experimenters had agreed with her ahead of the test that anything fewer than five matches did not "support any belief in her claimed abilities".
Professor Josephson said: "A statistically very significant result was obtained... but the experimenters concealed the fact with their talk of her failing the test."
Professor Wiseman said he agreed that the number of matches Ms Demkina had to achieve to be deemed a success was set higher than the standard probability of one in 20 normally used in psychology tests.
"We were asking her to jump high, but that was because her claim would present a huge challenge to science if it were true.
"I don't see how you could argue there's something wrong with having to get five out of seven when she agrees with the target in advance."
He added: "I'm not saying that this experiment was perfect or that all Professor Josephson's comments are wrong - like any first-time study conducted under the pressure of time and with limited resources it could be improved - but overall I think the results give us an additional insight into Natasha's claimed abilities."