Four little words to sort the wheat from the chaff

One question, central to the skeptical endeavour, is most likely to identify the real from the imaginary, the genuine from the fraudulent, and the merely deluded from the scam artist. Where claims are made, whether for the existence or power of deities, the efficacy of unusual medical treatments, or the reliability of money-making schemes, the one question that will provoke the most enlightening response is the question of evidence.

Suspicions will be initially aroused if claims lack substantiation. A request for substantiation is reasonable, but often the response is not. Unreasonable responses run the gamut from appeal to revelation (for deities) through conspiracy theory (for secret knowledge), pseudo-science (for nutritional supplements, young-earth creationism, infallible diets, the list goes on...), to legal action (for, amongst other things, alternative medicine).

"How do you know?" If we ask this question when presented with claims for, say, effective treatment for cancer, here are two possible responses (there may be others, but these are the important ones — the ones that tell us most about the motives of the responder).

Response 1: "We did tests. Here are the results. Judge for yourself."

Response 2: "Shut up, or we'll set the lawyers on you."

Time and again this four-word question — "How do you know?" — has separated genuine claims from those that are not. The latest example appears to be that of the Burzynski Clinic, offering a hugely expensive treatment for cancer with apparently no adequate scientific proof that it works — and this has been going on for over 30 years. A number of bloggers have raised doubts about Burzynski's treatment, questioning the evidence for its efficacy.

The Clinic's response: "Shut up, or we'll set the lawyers on you." It speaks volumes.