Sunday, March 18, 2007

"When does Skepticism become Denial?"

Wow hat tip to grisha on Skeptic Talk!

"When does Skepticism become Denial?"
by Steven Novella... M.D.!! No wayyyyyyy! M.D.! An M.D. that talks some sense! Sweet! Oh sorry, thats not the point of this post :P

A few great bits:
Regarding Science vs Pseudoscience

Philosophers of science often speak of the demarcation problem, referring to the difficulty of distinguishing consistently between science and pseudoscience. I am proposing that there are two subsets to this demarcation problem, between appropriately skeptical science and true belief or gullibility at one end, and absolute denial at the other.
At both extremes, gullibility and denial, the core of pseudoscience is the same - namely that pseudoscientists begin with a desired conclusion, and then go through the superficial motions of science to arrive at their predetermined conclusion. Whereas with healthy science inquiry precedes belief or condemnation. For deniers, their dedication to the denial of the offensive belief supercedes fair-minded skepticism. While attempting to portray themselves as skeptics, they are forced to employ a series of pseudoscientific tactics and logical fallacies to maintain their denial.

Regarding HIV Denial
The HIV denial literature reflects a basic distrust of authority and the institutions of medicine. Perhaps it is just the fascination of uncovering a conspiracy, or the psychological secondary gain of being involved in a righteous crusade. The AIDSrealitycheck website, for example, proudly displays the header, “This website is not brought to you by any pharmaceutical company.” At least in some cases there is a more direct secondary gain to HIV denial. Dr. Mohammed Al-Bayati, founder of Toxi-Health International, proclaims that “HIV Does Not Cause AIDS.” (Al-Bayati, 1999) Rather, he claims, it is caused by toxins, which his clinic is uniquely qualified to diagnose and treat.

The HIV deniers behave similarly to the psychiatry deniers. For example, one pro-HIV denial article states that semen samples from HIV positive individuals often contain the same concentration of HIV as does saliva, and yet HIV is allegedly transmitted by semen and not by saliva. (Farber, 1992) This is only partly correct, however. The article leaves out the important fact that intercourse creates small abrasions that allow for the virus to get into the blood stream, whereas the virus cannot penetrate the oral mucosa. In fact, if someone had a cut in their mouth then they could acquire HIV through saliva. Also, the rate of transmission of HIV is much higher in individuals who have other sexually transmitted diseases because they often have open sores which allow easier access to the virus.

Another common representation of the unreasonably far goalpost is the frequent demand by prominent holocaust deniers to be shown “one piece of evidence” which proves the holocaust happened. No one piece of evidence can establish such a complex historical event. Just as no one piece of evidence can establish that organic evolution happened on this planet. Not even the rather straight forward claim that HIV causes AIDS can be established by a single piece of evidence, it must be the result of a chain of evidence.
The HIV deniers have taken a similar stance. The correlation between the HIV virus and AIDS has been established beyond all reasonable doubt. Much is known about how HIV works, and drugs which specifically target retroviruses (the type of virus HIV is) have successfully prolonged survival and decreased opportunistic infections in HIV positive individuals. Yet this is not enough for the HIV deniers. They attack the pieces of the puzzle we don’t yet know, or which can only be inferred but have not yet been definitively proven. Why haven’t we seen the virus actually killing T-cells (the cells of the immune system targeted by HIV)?

Anti-HIV crusader, Dr. Peter Duesberg, has argued that HIV “fails to meet the postulates of Koch and Henle,” (Duesberg 1988) which were designed to establish criteria for demonstrating the link between an infectious agent and a disease. However, the Koch and Henle postulates were developed in 1840 and 1890 respectively, before viruses were even discovered. Biology has evolved far beyond Koch and Henle, whose postulates are no longer definitive.

They have also employed the “show me one piece of evidence” strategy. In fact, one HIV denier is offering a $10,000 prize (sound familiar) for anyone who can reference one article which demonstrates all the key elements necessary to establish HIV as the cause of AIDS. Typically, however, the research necessary to demonstrate such a connection would be spread out over many articles. The request is unfair and is made solely for its dramatic effect.

The HIV denial literature is also replete with similar claims of emerging skepticism. For example, Celia Farber wrote in a pro-HIV denial article, “More and more scientists are beginning to question the hypothesis that HIV single-handedly creates the chaos in the immune system that leads to AIDS.” (Farber, 1992) The article was published in 1992, and ten years later there remains a solid scientific consensus that HIV causes AIDS.

As part of this strategy deniers tend to rally around a figure head, a scientist insider who spearheads the denial movement. HIV deniers have virologist Dr. Peter Duesberg as their champion.


Kristjan Wager said...

"No wayyyyyyy! M.D.! An M.D. that talks some sense! Sweet!"

Comeon, don't make Orac cry.

ERV said...


I wish this article was newer (its 2002) so I could email it to him to cheer him up a bit!