The Modern Survival Guide #2

This is the Modern Survival Guide, a guidebook I’m writing for things I think people need to know about living in the modern world. The views expressed here are mine, and mine alone. In this article I’ll be talking about risk, and how we think about it, and why that’s important.

Modern humans are really bad at figuring out how risky things are. This can lead to weird choices. To put it bluntly, people often choose to do things, or choose to believe things, that make no sense from a risk-based perspective. This is important to you because we have a lot of numbers about a lot of events that happen to people — and in some cases, these events are the last things that happen to some people. You ignore a realistic risk assessment very literally at your own peril.

Let’s look at three common examples: the lottery, cars, and refugees.

Let’s start with the lottery. Millions of people play the lottery. I play the lottery. I go down to my local 7/11 every once in a while and buy a ticket. And I know, even as I do it, that I’m probably throwing money away (or, as I like to tell myself, contributing to my state’s education fund). But I buy a ticket anyway, because it’s fun to dream for a couple of days before the winning numbers come out and they aren’t mine.

But here’s the thing: a lot of people buy dozens of tickets, at significant personal cost, for the same lottery I buy one ticket to play. And they really are throwing money away. What’s going on here? Well, if you ask them, most of these folks will say “I’m improving my odds” or “I’m doubling (tripling, quintupling, etc.) my chances of winning.” And this is true. For a given value of true.

Your odds of winning the Powerball are something like 1 in 292,000,000. And this doesn’t improve until you buy a LOT (millions) of tickets. For everyone except very stupid millionaires, though, odds of 1/292,000,000 vs. 40/292,000,000 are not very different, in that they’re both so small that they’re functionally equally unlikely. But people still buy dozens of tickets at a go. Why?

The short version is that humans are bad at risk evaluation. Your brain is simply not set up to handle concepts like “millions of things,” but is very good at handling concepts like “if I buy two, I double my chances, because two is twice as much as one.” For most of our evolutionary and social history, we never had to deal with numbers in the millions; it was good enough for us to figure out odds in terms of tens or hundreds. If I’m twice as likely to get eaten by a lion near that watering hole, because I know that two hunters got eaten there as opposed to this other watering hole where only one hunter bit it, that’s enough for me to make a decision. But that concept does not scale up effectively.

It might be better to start thinking in terms of different categories when making these kinds of decisions. Categories like “certain,” “likely,” “sort of likely,” “unlikely,” and “infinitesimally rare.” That gives us a little more conceptual space to work with. So getting eaten by a lion on the savanna used to be unlikely, but still possible, while winning the lottery today is infinitesimally rare and virtually certain to fail.

Switching gears, let’s talk cars for a moment. Lots of people are scared of bees, wasps, mice, rats, snakes, and cockroaches. Hardly anyone is scared of cars. But if you had to pick, right now, which of those things would severely injure you (and let’s assume you’re not allergic), which one would you go for? It’s cars, hands down.

But nobody is scared of cars; we all go driving almost every day, or at least every week, in the US. Which is a serious issue, because something like 40,000 people a year die in car wrecks, and roughly 4.6 million are injured. That means you have a roughly 1.4% chance of being injured or killed in a car wreck every year (assuming a US population of 323 million). Over your lifetime, assuming you live to be 79 years old, that means you have a 100% likelihood of being in at least one injurious car wreck.¹

Being in at least one car wreck that injures you is therefore a near-as-calculable-certain event during your lifetime. But if you bought forty lottery tickets a month, every month, for your entire (average) lifespan, you’d still have only about a 0.01% chance of winning the lottery. That’s one chance in 10,000, give or take a bit. This is a very, very small chance, but people go all in on it all the time.²

Back to the point: most people get in a device every day which is almost certain to injure them at some point, and many people religiously play a game that has a ridiculously tiny chance at paying off. And they do not recognize the strangeness of this.

What’s going on here is a discussion of risk tolerance. We’re bad at figuring this out logically, without a lot of thought and training. You are very probably willing to tolerate a significant risk to your body in order to get to your destination faster. And you are also very probably willing to risk a small amount of money for a astonishingly tiny chance at winning a lot of money.

What about refugees, then? Well, it’s like this: There’s a roughly 0.0007% chance that any given refugee will attempt to carry out a terrorist act in the US. That’s about 3 refugees out of every 500,000, and that’s including the guys who don’t succeed. You may notice that this is less than your chance of winning the lottery after buying forty tickets a month for your entire life.³

And yet, we have an enormous segment of the US population who are perfectly happy to bar refugees from entering the country on national security grounds. Even though the US murder rate is 7 per 100,000, which means you’re roughly 10 times more likely to be murdered than any refugee is to try to commit an act of terrorism. Given that roughly 50% of murders are committed by someone known to the victim, that means that you are 5 times more likely to be killed by a friend or family member than a refugee is to attempt to commit an act of terror. And yet, a huge number of people think that refugees represent a major national security risk and are prepared to deny all refugees entry to the US based on that conclusion.⁴

Here’s my takeaway from all of this: Human risk calculations do not, as a rule, involve math. They involve emotion, and life needs, and sometimes a form of “common sense” logic… but rarely do people actually sit down and think in terms of calculated risk.

You drive a car because you want to get places faster, because you’d be bored walking, because you have to get to your job, or because you want the status that comes with owning a vehicle. The fact that the car comes with a substantial risk doesn’t matter as much.

You play the lottery because it’s fun to imagine what you’d do with all that money, or because you desperately need a lot of money. The fact that you are extraordinarily unlikely to win doesn’t matter as much.

You don’t want to admit refugees because all you see on television is news about violence and terrorism, and some of the people who want to come here originate in places where you have been told terrorists live. The fact that you’re in more danger from your friends and relatives doesn’t matter as much. Plus, refugees are usually some shade of brown, which may or may not have some resonance with your regard for them.

My mother has a saying: when emotions turn on, the brain turns off. She was a high school guidance counselor for years, so I assume she knows what she’s talking about; she’s seen a lot of brains switch off and a lot of emotions take over. But if you want to survive in modern society, you have to use your brain (if only because so many other people are quite happy to use your emotions for their own ends). And that means, sometimes, you need to do the math and decide whether you are going to accept a risk based on statistics, not on emotion.

If you want to calculate your risk of doing just about anything, the internet is your friend. For virtually any activity likely to result in your death, someone has kept track of its frequency. That’s how most government safety agencies defend their existence, after all. Any site with a .gov address is probably a safe bet to check on this kind of thing, but just to be sure, feel free to check out other sources. Just stay away from the propaganda ones — the internet is your friend in figuring that out too.

All you have to do then is trust numbers more than you trust your emotions, in order to live a less risky life, or at least understand your risks better. Simple, right? No, it’s not — you’re going to be fighting your emotions and “common sense” the whole way. Don’t let that stop you. So drive safe and don’t waste so much money on the lotto. And for God’s sake, let in some refugees.


There was a lot of math in this entry, so if you want to check my numbers, look below.


¹Assuming the US life expectancy is 79 years old, divide 4.6 million injuries caused by car wrecks (we’re rounding out the deaths) into 323 million (the estimated US population). That’s your annual chance of getting in an injurious wreck in the US. Multiple that number (4,600,000/323,000,000 = 0.014241486) by 79. That gives you 1.125. In statistics, you calculate percentages by moving the decimal place two spaces to the right once you’ve done this sort of calculation (1.0 = 100%). That means that a 79 year old human has a 112.5% chance of being in an injurious car wreck at some point in their lives. A 100% chance represents statistical certainty, which is not necessarily the same thing as actual fact — statistics are what should happen; luck is what happens to you. Meaning that you might get away with not getting hit, but it’s unlikely.

²In this case, I found the percent chance of winning the lottery by dividing 40 into 292 million (40/292,000,000 = 0.00000014). That’s your odds of winning if you buy forty tickets for any given Powerball lottery. Multiply that number by 12 to get your chances for a year’s worth of play (0.00000014 x 12 = 0.0000016). Multiply that number by 79 to get your lifetime chance (0.0000016 x 79 = 0.00013). Now move the decimal two places to the right to get your percentage chance of 0.013%. Remember that decimals calculate by tens, so 1% is one chance in a hundred, 0.1% is one chance in a thousand, and 0.01% is once chance in ten thousand.

³This is using as a source. Over the 41 year period from 1975 to 2016, the US admitted about 3 million refugees. Of that number, 20 were convicted of attempting or accomplishing a terrorist act during the same time period. So, to get the chances of any given refugee committing or attempting a terrorist act, divide 20 into 3 million (20/3,000,000 = 0.0000066). Then move the decimal. That gives you a 0.0007% (with rounding) chance.

⁴To calculate the chance of refugee terrorism vs. the chance of being murdered (note: not successful terrorism either, just any instance of a refugee being charged with terrorist acts), first divide 7 into 100,000 (7/100,000 = 0.00007). Move the decimal place to find the percentage of 0.007%. That’s your odds of being murdered. Since the rate of refugee terrorism is 0.0007%, we have a straightforward calculation of 0.007/0.0007 = 10, indicating that you are ten times more likely to be murdered than a refugee is to commit or try to commit a terrorist act.

Searching for truth in a world focused on belief.

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