Posted by Stephen Dubner quotes Gary Becker as saying:
According to the economic approach, therefore, most (if not all!) deaths are to some extent “suicides” in the sense that they could have been postponed if more resources had been invested in prolonging life.
Dubner describes this as making “perfect sense” and as being “so unusual and so valuable.”
When I first saw this I was irritated and whipped off a quick entry on the sister blog. But then I had some more systematic thoughts of how Becker’s silly-clever statement, and Dubner’s reaction to it, demonstrate several logical fallacies that I haven’t seen isolated before.
No, it’s not true that most deaths are suicides
I’ll get to the fallacies in a moment but first I’ll explain in some detail why I disagree with Becker’s statement. The claim that most deaths are suicides seemed evidently ridiculous to me (not just bold, counterintuitive, taboo-shattering, etc., but actually false), and my inclination in such settings is to mock rather than explicate–but Becker and Dubner are smart guys, and if they can get confused on this topic, I’m sure others can too.
To start with, the statement “all deaths are suicides” is hard to criticize because it is obviously wrong and must, like the Bible and much of the work of A. J. Liebling, be taken metaphorically. if somebody tells me that the temperature in Paris yesterday was 20 degrees C, I can argue, both from personal experience and the weather report, that it wasn’t. But if I tell Gary Becker that, no, I know his statement is wrong–both of my grandmothers died and neither of them committed suicide–that wouldn’t cut much ice with him. After all, he probably has a couple of grandmothers who died without committing suicide too.
Suicide is “the intentional taking of one’s own life.” Or, if we want to put a statistical spin on it, choosing an action that increases the probability that you’ll die sooner. I interpret Becker as saying that most (if not all) deaths arise from such a choice.
It’s not so simple, though. Consider the following example. A couple and their two children are driving on the interstate to Grandma’s house for Thanksgiving, a few hundred miles away, when all of a sudden a tractor-trailer jackknifes right in front of them, resulting in a crash that kills them instantly.
Ha! Becker might say, in response to this hypothetical example. Everyone knows that flying is safer than driving. If this family had really cared about safety, they would’ve flown. Instead, they drove, which reveals their hidden preference: they really care more about saving money, or convenience, or having the kids watch DVD’s in the back seat, or whatever.
I don’t buy this argument. Even setting aside the kids’ deaths here–were they committing suicide too? Are four-year-olds with leukemia committing suicide? etc?–and setting aside the possibility that maybe Mom and Dad didn’t happen to be aware of the stats on flying and driving, there’s a bigger problem here, which is that people die all the time, even while making statistically correct decisions.
For example, suppose this particular family had flown to Grandma’s instead of driving, but then the plane crashed. It wouldn’t make much sense to say that they’d made the suicidal decision not to drive! OK, maybe you want to push this back one more step and say that the suicidal decision was to visit Grandma at all. But what if they’d stayed home and Junior had cracked his head open falling out of his treehouse. Or maybe the solution is to stay inside? Certainly not! The suicidal result could be that Junior and Missy get no exercise and die young of heart attacks. Also, being stuck in the house all day, they don’t learn how to make friends; as a result, they don’t succeed in the business world, they can’t get a job with health insurance, and so on.
Another line of reasoning is that, if only their car had been a Sherman Tank, the family could’ve withstood the tractor-trailer impact–thus, the death really represents the Smith family’s unwillingness to pay more for safety. But this line of reasoning is wrong too, both on an individual and a societal level. A tank isn’t cheap, either to buy or to drive, and the resources spent maintaining the tank (thus reducing the risk of death on the highway) are resources that can’t be used to make one’s life safer in other ways.
Just to nail that down one last time, no, I don’t see the evidence that “most (if not all) deaths . . . could have been postponed if more resources had been invested in prolonging life.” Transferring resources to avoid death from cause A could very well increase the probability of dying sooner from cause B.
A bouquet of fallacies
Now for the fallacies. The “puzzle” (as we say in the social sciences) is the “stylized fact” (ditto) that a scholar as intelligent and accomplished as Becker, and a pundit as intelligent as accomplished as Dubner, could get something so wrong. I will consider some fallacies that may have led them astray. As usual with this sort of thing, I hope that the exposure of these fallacies will allow people to better avoid them in the future.
The smart people fallacy. Lots of important issues have smart people on both sides, so it’s clearly a fallacy to think someone’s correct just because he or she is “smart.” Remember, Isaac Newton believed in leprechauns! Well, not really, but you get my point. Gary Becker is smart, but he can make mistakes–and the “smart people fallacy” can lead him to compound his mistakes, if people who know him just assume he must be correct and don’t call him on it.
The transitivity fallacy. We all know that a friend of a friend is not necessarily a friend. But we tend to forget that this lack of transitivity also holds with knowledge. Dubner knows and trusts Levitt; Levitt knows and trusts Becker. So Dubner should trust Becker, right? Wrong. The problem here is that knowledge and trust are contextual. Dubner knows Levitt enough to know when to take Levitt seriously and when to ask him some tough questions. Similarly, Levitt knows Becker well enough to trust him and also to evaluate his arguments critically. But when Dubner cuts out the middleman and reads Becker directly, he also bypasses two stages of critical filtering. That’s the transitivity fallacy.
The fallacy of qualitative counting We can imagine ways in which individual deaths could’ve been avoided–more money spent on safety here, more preventive screening there–so it’s natural to think that these possibilities cover everything. But, as Zeno taught us, you can add up lots and lots of little things and still not get so far. (Bill James once made a similar point about all the different unlikely ways you can get to first base without a hit, but I can’t remember where or what exactly he said. His point was that sometimes people list all these possibilities without recognizing that some of them are extremely rare.)
The fallacy of forgotten tradeoffs I mentioned this one above, and it’s a funny error for an economist and an economic journalist to make. At some level, I think they were aware of opportunity cost–Becker’s idea is that people are trading off safety for convenience, or, more generally, for quality of life–but they didn’t see their argument through to the end and realize that, no, you can’t just trade everything else in life off for safety. To draw an analogy, if you make a car bigger (without changing its engine), it will go slower, but that doesn’t mean you can strip down a Ford Fiesta and make it go 250 mph.
The illusion of control
Let me conclude by bringing up something that affects many of us in our professional lives: the tendency to focus on aspects of our lives where we feel we can make progress. I think the illusion of control is what leads Becker to write about suicide using mathematical expressions of optimality followed by phrases such as “That is, where a ray from the origin is tangent to the utility function (see Figure 1).” In another era, we might dig up some rocks and build a burial mound with our bare hands; in this white-collar era, we express our frustrations with the world with our words and equations. (I’m not saying that Becker thinks that he can control suicides by writing his article; what I think is that, when faced with difficult items beyond our control, we keep ourselves busy doing what we can control.) I’m surely involved in my own illusion of control by writing about these fallacies, but just maybe they will lead to a better understanding of the role of mathematical models in the social sciences. Dubner and Becker have made a contribution by putting there ideas out there where they can be criticized and refined.
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