Fear and Probability

Re-posting this for all the beach-goers this Memorial Day weekend…

You are more likely to die driving your car than flying in an airplane. That’s right, you’re more likely to die while driving to the airport than to die in the plane you’re trying to catch. Why don’t more of us suffer from fear of driving?

Since 9/11, the US has spent somewhere in the neighborhood of $3 trillion to fight terrorism—about one-fifth of the federal budget. Do you feel $3 trillion safer? If you live in the US, there’s a one in four million chance that you’ll be killed on US soil by terrorists (and the terrorist who kills you is likely to be a white native-born male). That’s a lot of money for protection against an extremely remote threat.

How about the odds you’ll be attacked by a shark the next time you go in the ocean? You are more likely to die by falling down, catching the flu, getting hit by lightning or shot by a gun-toting toddler. You’re more likely to live to 100 than be attacked by a shark and more likely to get flattened by a comet or killed in a dog attack or by a bee sting. Cows kill more people per year than sharks. Homeowners with guns shoot more family members than they shoot burglars. What does that mean? Why is that significant? Does it mean armed homeowners are more dangerous than sharks?


What’s the real threat? We are, of course, and the in-born difficulty we have in keeping emotionally charged thoughts in perspective.

There are two problems with our thought processes when we’re dealing with probabilities, and these problems have been identified by psychologists and neuroscientists. The trouble comes from two cognitive biases we all suffer from: the availability heuristic and probability neglect. Remember, a cognitive bias is a sort of automatic way of thinking that isn’t always rational.

The availability heuristic (which is actually a bias, a habitual way of thinking) pumps up our anticipation of a possibility based on our emotional reaction to it. Our minds are functioning this way when we are imagining the grisly details. Falling down the stairs doesn’t seem as emotionally vivid as lots of sharp teeth and billowing blood. Getting the flu isn’t as emotionally provocative as getting gunned down by terrorists. Our emotional reaction to vividly imagining a possible event rather than the probability that it will actually happen is what sparks our reactions in these cases.

The other problem is known as probability neglect. Our minds have not evolved to deal very well with probability. This may be because there was no time for our ancestors to figure out the probability of being killed by a bear every time they saw one. The memory of that other poor guy who got shred to pieces is too strong. The result: our best guesses at probability usually cause our brains to shout RUN AWAY instead of calmly informing us there really isn’t much to worry about.

What to do? These two biases frequently mislead us. Awareness is the first safeguard—simply knowing our brains behave this way. Then it’s easier to catch ourselves doing it, although you may see it happening in others before you see it in yourself. Second, keeping track of our emotional reactions and asking ourselves if our reaction is commensurate to the actual threat can go a long way to keeping us fairly rational. And, of course, self-education about threat levels helps too. Everything I’ve stated here falls into the category common knowledge. If you were unaware of any of this, you may need to do a little more self-education.


Author: Craig Butcher

Craig Butcher is an award-winning educator who has taught critical thinking skills for more than two decades. In addition, he has worked on Capitol Hill as a congressional staffer and has been a top-rated broadcaster.