by Jeffrey Shallit
If you can't distinguish between science and pseudoscience, your life may be at risk. That's one of the lessons of the recent South African conference on AIDS.
In a complicated and dangerous world, science is one of the best tools we have to distinguish truth from falsehood; in the words of Carl Sagan, it is a "candle in the dark".
What do scientists do? They gather evidence and form hypotheses (educated guesses) to explain that evidence. They test their hypotheses by doing experiments. If scientists obtain good results, they publish in scientific journals, where their work is carefully scrutinized by the competition. Scientific results become accepted only if they are confirmed by independent laboratories. Every scientific conclusion is subject to revision, but paradoxically it is precisely this tentative nature that permits so much confidence in the scientific consensus.
But science is difficult and not always spectacular. So there's a parallel world that tries to trade on the prestige of science without doing all the hard work that science demands: the world of pseudoscience. Not everyone can distinguish the two.
The claims of pseudoscience are many: crystals heal disease, dowsers can find underground water by holding a pointed stick, aliens routinely visit earth and abduct humans for their experiments, magnets on the skin offer pain relief. You might think these claims don't merit much attention --- after all, they are silly, unsupported and relatively harmless. But recently, pseudoscience has taken a deadly turn, putting forth the claim that HIV does not cause AIDS.
The HIV-AIDS link is firmly established, supported by dozens of published studies over the last 15 years. Nearly every epidemiologist is convinced. A recent declaration published in Nature stated that "The evidence that AIDS is caused by HIV is clear-cut, exhaustive and unambiguous, meeting the highest standards of science."
Despite the overwhelming evidence, South African president Thabo Mbeki has chosen to side with the pseudoscientists in denying that HIV is the cause of AIDS. If AIDS is not caused by a sexually-transmitted virus, there would be no need to tell people to use condoms or take other protective measures. It wouldn't be necessary to buy AZT or other expensive anti-viral drugs.
These savings may sound attractive to the leader of a poor country, but wishing does not make it so. The result is that 24 million people in South Africa are now HIV-positive. Pseudoscience can truly be lethal.
Comedian Andy Kaufman was another victim of pseudoscience. Afflicted with lung cancer, he gave up on traditional medicine and instead flew to the Philippines, where he was operated on by a "psychic surgeon". These fraudulent practitioners prey on the hopeless, pretending to remove diseased tissue while actually producing chicken entrails hidden in their hands.
How can the average person distinguish pseudoscience from science? It's not always easy, even if you're a professional scientist. But here are some suggestions.
First, pseudoscientists generally do not publish articles in reputable scientific journals. Instead, they publish books with political or religious publishers. For example, Michael Behe's recent anti-evolutionary tract, _Darwin's Black Box_, was published by the Free Press, a right-wing political publisher.
Second, pseudoscientists often don't have advanced degrees in the areas they write about. For example, one of the most prominent opponents of evolutionary biology is Phillip Johnson, a Berkeley lawyer without any biological training. (Johnson -- who also has no medical degree -- is another who denies the HIV-AIDS link.)
Distinguishing pseudoscience from science is hard work, but the alternative can be fatal.