Two years after challenging a selection of religious fundamentalists to justify their beliefs in Channel 4’s The Root of All Evil,Richard Dawkins – “Darwin’s rottweiler” – is growling again. This time, in The Enemies of Reason, he takes on the wider penumbra of the paranormal, New Age mystical mumbo-jumbo, and the often expensive spiritual services that bring succour to the sucker.

His targets include astrologers, psychics, dowsers, homoeopaths and a woman called Elisis Livingstone who claims that in our Atlantean past we all had 12 strands of DNA rather than two. If the thought of being ten strands short bothers you, Livingstone claims she can restore them.

What makes Oxford University’s Professor of the Public Understanding of Science different from most sceptics, rationalists and humanists is that he won’t let this stuff lie. If someone claims that they can “channel” the spirits of the dead or alleviate the symptoms of some horrible incurable disease by pointing beams of coloured light at your chakras, Dawkins does not want to dismiss it as harmless fun. He wants to know how they claim to do it and what hard evidence they can produce to show that the effects they say they produce actually occur. This may seem like taking a steamhammer to smash a peanut, and Dawkins is aware that some people see him as a kill-joy, but for him the fun is not harmless. “We live in dangerous times,” he says at the start of the first show, by which he means not just the threat from, say, Islamic fundamentalism, but a more general flight from reason and the scientific method. Speaking at his office in Oxford, he says that the decline in interest in the physical sciences in schools is tragic. “The lack of scientific education means that people are not armed, not equipped to see through irrationality.”

Much of the material may seem familiar to interested sceptics: the practice of cold-reading, whereby “psychics” pick up cues from their audience’s reactions to a scattering of vague words and phrases and use them to make people imagine they have been told something that relates specifically to them. Or the fact that homoeopathic remedies are claimed to work despite containing not a single molecule of the supposed active ingredient. (Dawkins points out that it is statistically almost certain that at least one molecule of every glass of water we drink will have passed through Oliver Cromwell’s bladder.)

The programmes feature a series of confrontations with assorted paranormal professionals who are asked to explain the basis behind their belief and whether it has ever been scientifically tested. Unlike The Root of All Evil, when some encounters generated more heat than light, he is unfailingly good-humoured and polite. “In some cases I just lost it,” he says of the religious series. “Perhaps this time it is a bit less confrontational.”

The one real row was with a psychic he consulted at a New Age fair, who told him she was in contact with Dawkins’s “dead” father in the spirit world and relayed a message in some detail. “I sat there po-faced and let her go on for quite some time before I said, ‘Actually my father is alive and well and living in Oxfordshire.’ Immediately she said, ‘Stop the camera!’ and tried to terminate the whole thing. To my disgust we had to cut her out of the programme for legal reasons, which is a great shame. She was a real charlatan.”

So how many of these practitioners are crooks? “The psychics, I think, mostly are,” he says. “But with one spiritualist I couldn’t make out if he was a charlatan or not. It’s possible that they sort of know that they’re cold-reading, but they still think it’s the spirits channelling through them.”

However, the water diviners were “genuinely sincere”. In a rather touching sequence a group of dowsers agree to submit to a double-blind trial. Their success rate in finding water was about what you would expect by chance. “In some cases they were devastated that they couldn’t do it under those conditions.”

And what of the more bizarre medical beliefs, such as the Atlantean DNA strands?“I think there’s a kind of mind that is so devoid of realism that they’re prepared to believe essentially anything,” he says.

His patience appears particularly stretched by Neil Spencer, The Observer’s astrologer, who argues that he would not subject his work to scientific tests because the aim of the testing would be to cause “mischief”.

Dawkins can’t hide his frustration at people’s gullibility. “The science of astronomy is so mind-shatteringly elegant and beautiful and inspiring, that this is demeaning and shallow and a betrayal of what it is to be human, when the human species has achieved so much in understanding the universe.”

The Enemies of Reason, Mon, Channel 4, 8pm

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