Free The Canon by Natalie Angier Page A

believe about the stories. They examine the articles again, this time with more care. Well, it's just ... why
should
I believe it?
    Nolan then shows them the original journal studies on which the newspaper stories were based, and she and the students begin, methodically, to pick the studies apart. They consider who the research subjects were, whether the participants were divided into two or multiple groups, the basis on which they were assigned to one group or another, and how the groups were compared. They discuss the strengths and limitations of the study, and why they think the researchers designed it as they did, and what the students might have done differently if they were running the study themselves. Enlightened now with this insider's intelligence, the students then reread the newspaper stories, to see if the reporters accurately conveyed the essence of the studies.
    Most of the time, Nolan said, the students are impressed and appreciate that the reporters did their jobs after all, a change of heart that so surprised me I had her repeat the words slowly and clearly and right into my tape recorder.
    More to the point, when the students come across an example of ineptitude, they can articulate why they feel dissatisfied. "They started off being highly skeptical of everything they read, without knowing quite why," she said. "But as critical thinkers, they could back up their comments and misgivings with precise descriptions of what was in the original study and what was omitted."
    I also like Bess Ward's method for converting her students from cynical derision to clinical precision. Ward is a professor of geosciences at Princeton University, and every year she tells her students, Pick a worry, any worry. She has them pose a question about an everyday concern of theirs, a personal habit or indulgence or preferred food that they may have heard or read a negative report about. Their task is to figure out, Should I really worry, or not? How big a risk am I taking if I continue to eat or act as I do, and how does this risk compare to other risky behaviors that I freely or of necessity engage in? Or should I feel guilty about my little luxuries because they may be harming others, or are bad enough for the environment that I can't quite justify them?
    "I tell them, choose something that you relate to and that may sometimes nag at you from the background of your mind. Drinking a lot of coffee, or taking birth control pills, or eating tuna sandwiches, or bungee jumping," she said. "The idea is, look at the evidence and do a risk assessment."
    For most of these concerns, the basic data points, the worry wartlets, are accessible on the Internet. The Environmental Protection Agency's Web page, for example, offers so-called reference doses for virtually every toxic chemical you're likely to encounter—scientific estimates of how much of the chemical you can be exposed to without suffering harm. Here you will find the average concentration of mercury in an average Charlie tuna presented as milligrams of toxin per kilogram of fish. You will also find how many milligrams of mercury a person can safely ingest per kilogram of his or her own body weight before needing to worry about achiness, bleeding gums, swelling, blindness, coma, and, well, I think I'll just go with the arugula salad, thanks.
    Or let's say you're fretting, as one of Ward's students did, over the relative riskiness of a weekly manicure. When you're in a nail salon, you're breathing in all the fumes from nail lacquers and the solvents that remove them, an ambient nosegay only slightly more sensual than that of the elephant facility at the National Zoo. But is obnoxious necessarily noxious? On the EPA Web page, you will discover that nail polish and polish remover contain toluene, a moderately toxic petroleum extract that also happens to be moderately volatile—i.e., it evaporates easily into the air you'll soon be breathing. The EPA also offers figures on