There is a chance, while you're reading this, that your computer explodes. There is also a chance that your roof collapses, a wolf breaks through your front door and eats you, an alien pod sucks you up through an alternate dimension you didn't even realize existed, or a sudden giant sinkhole engulfs your house. That's all to say, everything we do, including "nothing," carries with it some risk. An inherent truth of the human condition: it will end. When that will happen depends on an unquantifiable number of factors—but the factors themselves? Actually quantifiable!
In their new book The Norm Chronicles, Michael Blastland and David Spiegelhalter tell the story of three characters—Prudence, Kelvin, and Norm—through a number of situations. The book teases out and explains the risk accompanying a number of everyday scenarios, while explaining how different people might react. The main unit of risk-measurement is the MicroMort, which is a one-in-a-million chance of death. For example, a soldier in Afghanistan faces 47 MicroMorts a day, while giving birth exposes a mother to 120 MicroMorts. The three characters then make their decision by either weighing the risks of a given situation, being paralyzed by them, or just not caring at all.
We spoke to Michael Blastland about his book and about being aware of risk in the world.
So, this is a generic start-off question here, but I think it's a valid one, as writing a book like this would probably make you consider your own mortality more frequently than others. What made you write this book about risk and the probability of death?
Think of it as a book about chance and danger and who can resist? Fun as well as fatal, feeding hope as well as fear, it's a gloriously rich subject. Every film, the half of news that isn't about celebs, no end of life choices and not least the everyday ones—whether you should have that third glassful, take the kids by car or take that corner too fast, or sleep with so-and-so—are loaded with questions and assumptions about chance.
Risk can also be a tyranny—with death and danger seemingly lurking behind every lamppost—and it can sometimes feel as if every news source and authority wanted to make us the slaves of nightmares. The way most of this is communicated, at least in the U.K., is horrible: confusing, often alarmist, often innumerate. We thought a couple of neat ideas could make it clearer—the MicroMort and MicroLife—cheery little units of fatal risk to help put it all in proportion. We also wanted to break some rules and mix the stats with the more human, storytelling side of chance and danger. And we wanted to throw in a couple of big ideas—like probability not existing. So I guess you could say we were motivated by reckless bravado to explore this richness by bringing these many different perspectives together, since that seems to us to be what risk really is: a great clash of diverse perspectives.
"Being seven years old today in the U.K.—and probably the U.S., too—turns out to be about the safest thing anyone can be, ever."
What can people gain from being aware of the inherent risk in everything they do?
Well, survival, for one. Good health, another. If that's what they most want. But mainly they can make choices for themselves and their families equipped with some data. We're absolutely not telling people how to live. And since we also talk about the upside to probability, chance, and coincidence, people might, dare we say it, enjoy themselves. This stuff is also plain entertaining. Well, I think so. Partly because disasters and close shaves make great yarns. More seriously because the tussle between the data/probabilities on one hand and the psychology and storytelling about danger on the other seems to touch something deep in our general attitudes to life. Reflecting on all that is fascinating.
There needs to be some balance, so you're not, you know, calculating every breath you take, right?
Actually, we're working on the app for that right now. But sure. One problem with probabilities is the limit of human cognitive capacity. No one can live without a few mental shortcuts here or there or, to put it another way, such non-probabilistic analysis as “nah, don't fancy it”; or on the other side a kind of “what the heck” heuristic. So I'm off to cycle up some hills on the bike later even though I fell off a couple of days ago. But, you know, what the heck. I won't be completing a hazard assessment. On the other hand, I do know the data for cycling accidents, and I know the arguments about helmets, and they also lurk somewhere in the mental soup in which judgments are formed. And how they're formed is interesting.
On the whole, is an average day more or less risky than people might imagine?
It's 23 percent less risky than 31 percent imagine and 17 percent more risky than 42 percent imagine, with the remaining percent about right. Which is another way of saying that there is no way of running a ruler over people's accuracy. Yes, they can be right or wrong about the average probabilities, at least so far as we know them. But that's a small part of the problem. What people mean when they say something's risky is also often packed with other values and preferences for things like a feeling of control (at the wheel of a car rather than as a passenger in a plane, for example). On top of which, their own behavior can make, say, crossing the road, more or less risky than the current average probabilities of being run over. So risk is also contingent. For these and other reasons, a large part of people's sense of risk has to be subjective. In fact, we'd go so far as to say that objective risk for an individual, thought of as an independent property of the world out there, doesn't exist. We prefer to think of risk as typically more like an uncertain bet on a horse using scraps of imperfect information mixed with your own judgment: the horse might come in, or it might not....
What activities surprised you the most in their riskiness and non-riskiness?
Radiation fades fast with distance. Even so, learning that an all-body CT scan exposes you to about as much radiation as standing a mile and a half from the epicenter of the Hiroshima atomic bomb is pretty arresting. Looped window blind cords turn out to be more hazardous than you'd think. And being seven years old today in the U.K.—and probably the U.S., too; I must check the data—turns out to be about the safest thing anyone can be, ever. At least based on the average probabilities. So qualified though it often is, the data is still the hard stuff, even if people also then filter it in various ways.
Of the characters in the book, which one do you personally most associate with?
There's something of all three—Norm, Prudence, and Kelvin—in both of us. They've even become a sort of shorthand for the various ways we react from time to time. So I'll read something in the paper and say “that's a bit Prudence,” or maybe “frankly, I feel pretty Kelvin about that one.” But I do have a soft spot for Norm. He's a bumbling heroic failure who fancies that he can use pure information to soar above human anxiety, but always falls back to Earth, a kind of Icarus in a cardigan. Is that me? Scary.
What is the risk associated with writing a book about risk?
Huge. Or rather, on top of all the other reasons why it might die a horrible death, the risk in a book that combines the two worlds of numbers and stories is that it asks for a critical kicking from anyone on either side who has it in for the other. We hope to bring them together. But if you hate quantitative data and think it reductive and inhuman, or if you think storytelling is an irredeemable failure of logic, a habit of psychological distortion, you're not going to appreciate an attempt to link them that says in a subject like risk they're both vitally at play. So it's an unusual book, and that's always risky, but no one forced us to do it. Even so, straight after this, I'm digging a bunker in the backyard.