Risk: Why We Fear the Things We Shouldn’t—and Put Ourselves in Greater Danger
by Dan Gardner
“One of the most consistent findings of risk perception research is that we overestimate the likelihood of being killed by the things that make the evening news and underestimate those that don’t. What makes the evening news? The rare, vivid, and catastrophic killers. Murder, terrorism, fire, and flood. What doesn’t make the news is the routine cause of death that kills one person at a time and doesn’t lend itself to strong emotions and pictures. Diabetes, asthma, heart disease.”
Head and Gut. “People know what they like, what they fear, and so on. But what’s the source of these judgments? Typically, it is the unconscious mind—Gut… Gut is a black box; Head can’t peer inside. And when a researcher asks someone to say why she feels the way she does about a risk, it’s not Gut she is talking to. It is Head… Now, if Head simply answered the researcher’s question with a humble ‘I don’t know” that would be one thing. But Head is a compulsive rationalizer. If it doesn’t have an answer, it makes one up.”
Gut is bad with numbers. “A curious side effect of our inability to feel large numbers—confirmed in many experiments—is that proportions can influence our thoughts more than simple numbers… When Paul Slovic asked groups of students to indicate… to what degree they would support the purchase of airport safety equipment, he found they expressed much stronger support when told that the equipment could be expected to save 98% of 150 lives than when they were told it would save 150 lives.”
“‘It’s worth it if even one life is saved’ is something we often hear of some new program or regulation designed to reduce a risk. That may be true, or it may not. If, for example, the program costs $100 million and it saves one life, it is almost certainly not worth it because there are many other ways $100 million could be spent that would certainly save more than one life.”
Which is better: a 68% chance of being alive a year after surgery or a 32% chance of dying? “Framing the decision in terms of staying alive resulted in 44% opting for surgery over radiation treatment, but when the information was framed as a chance of dying, that dropped to 18%.”
Possible or Probable? “Saying that something could happen is close to meaningless. What matters is how likely something is to happen.” The author writes about denominator blindness. “The media routinely tell people ‘X people were killed’ but they rarely say ‘out of Y population.’”
“Risk regulators use a term called de minimis to describe a risk so small it can be treated as if it were zero. What qualifies as de minimis risk varies, with the threshold sometimes as big as one in 10,000, but a one-in-a-million risk is definitely de minimis.”
“Certainty, for example, has been shown to have outsize influence on how we judge probabilities: A change from 100% to 95% carries far more weight than a decline from 60% to 55%, while a jump from 0% to 5% will loom like a giant over a rise from 25% to 30%. This focus on certainty helps explain our unfortunate tendency to think of safety in black-and-white terms—something is either safe or unsafe—when, in reality, safety is almost always a shade of grey.”
“Uncertainty is so central to the nature of science that it provides a handy way of distinguishing between a scientist talking as a scientist and a scientist who is using the prestige of his white lab coat to support political activism: Look at the language. If a scientist delivers the simple, unconditional, absolutely certain statements that politicians and journalists want, he is talking as an activist, not a scientist.”
Herding. “It seems reasonable to think that when like-minded people get together to discuss a proposed hazardous waste site, or the breast implants they believe are making them sick, or some other risk, their views will tend to coalesce around the average within the group. But they won’t. Decades of research has proved that groups usually come to conclusions that are more extreme than the average view of the individuals who make up the group.”
News media. “The media are among those that profit by marketing fear—nothing gives a boost to circulation and ratings like a good panic—but the media also promote unreasonable fears for subtler and more compelling reasons. The most profound is the simple human love of stories and storytelling. For the media, the most essential ingredient of a good story is the same as that of a good movie, play, or tale told by the campfire: It has to be about people and emotions, not numbers and reason. Thus the particularly tragic death of a single child will be reported around the world while a massive continuing decline in child mortality rates is hardly noticed.”
Downsizing of newsrooms compounds the problem. “Reporters are increasingly asked to do more in less time and, as a result, they commonly do not read the studies they write about. What they read is the press release.”
Be patient. “The rhetoric surrounding disease mongering suggests that it will promote health,’ writes Iona Heath, a British physician, in the Public Library of Science Medicine, ‘but the effect is in fact the opposite. Much disease mongering relies on the pathologizing of normal biological and social variation and on the portrayal of the presence of risk factors for disease as a disease state itself. When pharmaceuticals are used to treat risk factors, the vicious circle is completed because anyone who takes medicine is by definition a patient.”
Better living… through chemistry. “Consider chlorine. Treat drinking water with it and it creates byproducts that have been shown to cause cancer in lab animals in high doses and may increase the cancer of people who drink the water. There’s even some epidemiological evidence that suggests the risk is more than hypothetical. So the precautionary principle would suggest we stop putting chlorine in drinking water. But what happens if we do that? ‘If you take the chlorine out of the drinking water, as was done in South America, you end up with an epidemic of 2,000 cases of cholera,’ says Daniel Krewski. And cholera is far from the only threat. There are many water-borne diseases, including typhoid fever, a common killer until the addition of chlorine to drinking water all but wiped it out in the developed world early in the 20th century.”
“We must also accept that regulating risk is a complicated business. It almost always involves trade-offs—swapping typhoid for carcinogenic traces in our drinking water, for example. And it requires careful consideration of the risks and costs that may not be so obvious…”
100% Natural. “‘People have this impression that if it’s natural, it can’t be harmful, and that’s a bit naïve,’ says Bruce Ames. ‘The other night in Berkeley, I noticed they were selling a bag of charcoal briquettes and it said ‘no artificial additives, all natural.’ And it’s pure carcinogen!’”
What to do? “While we may not be able to cut the circuitry of fear, we can at least turn down the volume. The first step is simply recognizing that there are countless individuals and organizations that have their own reasons for inflating risks, and that most journalists not only fail to catch and correct these exaggerations, they add their own. We need to be skeptical, to gather information, to think carefully about it and draw conclusions for ourselves.”
Gardner, Dan. Risk: Why We Fear the Things We Shouldn’t—and Put Ourselves in Greater Danger. Toronto: Emblem, 2008. Buy from Amazon.com
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