Mostly wrong, but never in doubt

How do quacks and charlatans so easily gain the confidence of their victims? I have long believed that the answer was to found in their ostensible utter confidence in their products. Rarely will these hucksters admit to any doubt about the scientific merits of their snake oil, in fact most could't care less. Hat tip to Tracy Allison Altman from Evidence Soup for pointing me to scientific evidence to substantiate my view.

A simposium of the Association for Psychological Science entitled Often in Error, Rarely in Doubt provided some answers. Don Moore, the chairperson, summarised the conference as follows:

"Excessive confidence in the precision of one’s knowledge is both the most robust and the least understood form of overconfidence. This symposium investigates its ultimate causes. The evidence suggests that overprecision is caused by limitations on the working capacity in human memory, conversational norms, and social pressure."

I would have liked to add greed and gullibility, but that is just my opinion.

A hat tip again to Evidence Soup for the article Humans prefer cockiness to expertise in the NewScientist. Quoting Don Moore, the article points out that people tend to believe the more confident message, regardless even of a poor track record of the messenger. This creates difficulties for scientists who, ethically acknowledging the limits of their knowledge, will always be at a disadvantage against activists and lobbyists.

I would extend this to the medical and educational arenas, where individuals who emphasize the necessity of evidence supported practices will always be at a disadvantage to unscrupulous quacks who ostensibly have no doubt about their scams.

There are also legal reasons for quacks not to admit to any doubt about their snake oil cures (and for critics not to allege that quacks know they're quacks). A case in point is the legal battle about libel between Simon Singh and the British Chiropractic Association (BCA). The key issue is this battle revolves around the word bogus. The judge ruled that in using the word bogus, Singh implied that the BCA knew that their cures were worthless. Read about it in my post UK chiropractors sue themselves in the foot.