Sunday, October 29, 2006

THE CONSENSUS VIEW IS FREQUENTLY VERY WRONG INDEED

One of the most misguided ideas in any debate is the idea that the consensus view is usually, if not always, right. All too frequently the accepted wisdom has been completely and comprehensively wrong. We may react with disbelief that anyone believed, or indeed still believes, that ships would sail over the edge of earth, and possibly be gobbled up by monsters, because the earth was flat. But historically this has been an accepted wisdom. And we may be bemused, even a trifle alarmed, that Galileo was threatened with the torture because he supported Copernicus's revolutionary (no pun intended) theory that the earth goes round the sun rather than vice versa. But Copernicus's maverick theory challenged a consensus that was politically dangerous to challenge.

Economics, albeit more prosaically, has also been subject to fads, whims and consensus views to which history has not been kind. Twenty-five years ago Britain was at an economic crossroads. The credibility of the British economy was collapsing as inflation and unemployment soared, manufacturing output slumped and the national debt spiralled upwards. Margaret Thatcher and her Chancellor, Sir Geoffrey Howe, concluded that drastic action was required. Taxes were raised by £4bn (then a huge sum) in the 1981 Budget in order to provide scope for lower interest rates and tackle public sector borrowing. There was, unsurprisingly, substantial political opposition.

But, of more interest, 364 economists signed a letter to The Times stating that there was "no basis in economic theory or supporting evidence" for Sir Geoffrey's policy and that it threatened Britain's "social and political stability". An alternative course of action must be pursued, these savants insisted. Almost the entire academic economic establishment stood against the Government with a mere handful of brave "mavericks" dissenting from the consensus view. But, as we now know, the letter's signatories were wrong because they believed in the then ubiquitous, but faulty, Keynesian consensus of the time.

Moreover, not only did the economics establishment regard Sir Geoffrey's Budget as fundamentally flawed, they also took the same view of the mavericks' judgments. This is instructive. Many in academia seem to believe that "peer-reviewed" research guarantees impartial, sound and independent assessment. It does not. Mavericks can be marked down and dismissed by their consensus-minded peers. Dissension is rarely popular.

The story of the 364 economists should be a warning to all who give the impression that the consensus view is an impregnable fortress of truth. Yet only recently Sir David King, the Government's Chief Scientist, was again reassuring us that at a meeting in Monterrey, Mexico, there had been a "scientific consensus" about climate change. Man-made carbon emissions were the main drivers of global warming. But the meeting was organised by the British Government to discuss the climate change action plan agreed at Gleneagles last year and the main protagonists were G8 ministers, hardly independently minded free spirits.

By happy coincidence, as the G8 delegates were flying to and from Monterrey, liberally scattering carbon emissions into the ether, the Royal Society was publishing a paper by a team from the Danish National Space Center (DNSC) of the utmost scientific significance. Interestingly, the DNSC team leader, one Henrik Svensmark, has been impeded and persecuted by scientific and government establishments in recent years because his findings have been politically inconvenient. Politically inconvenient they are indeed.

Very briefly, the latest DNSC research shows how cosmic rays from exploding stars can encourage cloud formation in the earth's atmosphere. As the Sun's magnetic field, which shields the earth from cosmic rays, strengthened significantly during the 20th century the average influx of cosmic rays, and hence cloudiness, was reduced over this period. The resulting reduction in cloudiness, especially low-altitude clouds which have an overall cooling effect, could, therefore, be a highly significant factor in the last century's global warming.

I am no climate scientist. But it is clear this research seriously challenges the current pseudo-consensus that global warming is largely caused by manmade carbon emissions. All the current carbon hysteria is a mistake - and a potentially costly one at that.

I have to admit I have some reservations about the Royal Society. They have sorely misrepresented me in the press at least twice. And they have frequently been accused of being the Government's mouthpiece on the science of global warming. After all, 67pc of their funding, some 30 million pounds, comes from Government. They have also, apparently, been accused of denying funding to any climate scientist who does not share their alarmist views. But, in publishing this research, they have added to a debate that has major economic and business implications for this country. They should be applauded.

Source






Perfect smile dangerous



In the quest for the perfect Hollywood smile, they provide an instant and cheap makeover for the mouth. But the teeth-whitening kits used by thousands of Britons who want polished molars can cause permanent damage, according to dentists. Super-strength whitening kits that promise to create brighter smiles by bleaching teeth with high levels of hydrogen peroxide dye can lead to chemical burns and aggravated gum disease, the British Academy of Cosmetic Dentistry (BACD) announced yesterday. The do-it-yourself kits, on sale over the counter in Britain for as little as 10 pounds, are in demand as an alternative to surgical bleaching treatments offered by dental clinics at a cost of between 300 and 1,300 pounds.

Yet some kits available online are 250 times more concentrated than the legal limit and can cause damage or over-bleaching, resulting in so-called "fridge door teeth", clinicians claim. At worst, they may exacerbate gum disease, leading to tooth loss. Private dental clinics are burgeoning, with the market for cosmetic dentistry in Britain now said to be worth 1 billion. More than a quarter of Britons have had cosmetic dental work, including caps and braces. However, whitening treatments are the most popular, according to a recent survey. James Goolnik, a dentist and board member of the BACD, said that the kits offering a "cheap, quick fix" were ineffective and offered a false economy.

"Whitening is a bit like a facial in that it helps to unlock pores in your tooth so that stains are gently removed leaving teeth cleaner and brighter," he said. "All whitening is based on a hydrogen peroxide solution; the only difference in the hundreds of systems out there is the concentration and the way the solution is applied to your teeth. Not all of them are safe. "By law, shop-bought kits in the UK can't have a hydrogen peroxide concentration level more than 0.1 per cent. But other countries have no regulations at all."

Dr Goolnik said that take-home kits should be used with caution since they involved using poorly moulded mouth guards, often worn overnight, allowing leakage of gel or solutions containing hydrogen peroxide, a chemical typically associated with hair colourings, into the mouth. "If the gel goes on to the gums, it can cause blistering. In someone who has got irritation or decay, it can accelerate the process," he said. Dr Goolnik said that the kits with high levels of hydrogen peroxide were designed to be used by professional dentists, painted directly on to the teeth while the gums were protected. He said: "We are seeing more and more people coming in with damage caused by whitening kits . . . They go to the supermarket and see whitening toothpastes. There is no evidence they can actually whiten teeth and people might not see a difference, so they want the next thing up. At best they get no result, and at worst they get permanent sensitivity. "It is essential to invest, at a bare minimum, in going to see your dentist before you use one of these kits, but you don't want to spend money on whitening for no effect and only a dentist can get your teeth to the maximum whiteness."

A spokesman for the General Dental Council, which regulates dentistry in Britain, said: "Tooth-whitening products contain bleach and need to be handled with caution. Only registered dentists are permitted to apply materials and carry out procedures designed to improve the aesthetic appearance of teeth." Carmel McHenry, a spokeswoman for the British Dental Association said: "Liquids that discolour teeth will darken them again over time." She recommended a full dental assessment before the procedure.

A spokesman for Boots the Chemist, which sells its own brand of whitening kits, said: "People with sensitive teeth or gums are advised to talk to a dentist before using whitening kits, and all users are advised to pay careful attention to the detailed instructions on the packaging. Our own-brand kit uses a non-peroxide formula and has been extensively tested and passed as safe to use."

Source

1 comment:

Thomas Palm said...

The idea that people believed the Earth is flat is a myth. As far back as there are any written records people have been well aware that it was round. The first known calculation of its size was made by Eratosthenes as early as around 200 BC. Sailors feared open water not because they might fall off the edge but becasue of storms or running out of supplies. (Had Columbus not found America they would all have died because they sailed until they didn't have enough supplies to return. The sailors had every reason to be scared).

When it comes to Svensmark you might want to read this description of what he did and more importantly what he didn't do. It's not time to scrap any consensus yet:
http://www.realclimate.org/index.php/archives/2006/10/taking-cosmic-rays-for-a-spin/

Despite what you say, if you are not an expert in a field it does makes sense to believe those who are. For every time the consensus turn out to be wrong there are thousands when the people who opposed it were wrong.