Trolleys, Ethics, and Obesity

Hidden irony attracts us. In the midst of a recent New York Times op-ed about studies of inconsistent ethics was data on people who “found it more acceptable to push a fat man in front of a trolley” than others did. It’s not often you see the words “fat man” in a newspaper these days. It’s even less often that you read about studies on the ethics of pushing one in front of a trolley. And the irony is this: social psychologists and philosophers have been using the “fat man and the trolley” thought experiment for 37 years as a standard tool for research in ethics and morality, seemingly giving little thought to the implications of introducing anti-fat bias into the mix. All this sits in the middle of a commentary on inconsistent ethics.

Philippa Foot first introduced “The Trolley Problem” as a thought experiment in ethics with a publication in the Oxford Review in 1967. The base version of the problem goes like this:

Edward is the driver of a trolley whose brakes have just failed. On the track ahead of him are five people. The banks are so steep that they will not be able to get off the track in time. The track has a spur leading off to the right and Edward can turn the trolley onto it. Unfortunately there is one person on the right-hand track. Edward can turn the trolley, killing the one. Or he can refrain from turning the trolley, killing the five. What should he do?

In 1976, Judith Jarvis Thomson published a treatise on moral dilemmas that introduced the “Fat Man and the Trolley” variant of the trolley problem. Philosophers and social psychologists have been studying it ever since:

George is on a footbridge over the trolley tracks. He knows trolleys and can see that the one approaching the bridge is out of control. On the track behind the bridge there are five people. The banks are so steep that they will not be able to get off the track in time. George knows that the only way to stop an out-of-control trolley is to drop a very heavy weight into its path. But the only available, sufficiently heavy weight is a fat man, also watching the trolley from the footbridge. George can shove the fat man onto the track in the path of the trolley, killing the fat man. Or he can refrain from doing this, letting the five die. What should he do?

These thought experiments were proposed to illustrate a moral distinction between killing someone (pushing them off a footbridge) or letting them die (redirecting the trolley onto the track with only one person). Substituting the language of  “a large man” for the more blatantly offensive “fat man” language, psychologists found people generally respond that letting someone die is more acceptable than killing someone to save others. One exception is upper-income subjects who, in a recent study, found it more acceptable to push the man onto the tracks than lower-income subjects.

That leaves us with one question. Whether they talk about a “fat man” or a “large man,” why do these intelligent social psychologists and philosophers unnecessarily introduce weight bias into the subject?

Click here to read the NY Times op-ed on our inconsistent ethics, click here to access Thompson’s treatise on moral dilemmas, and click here to read more about our moral instincts.

Go by Streetcar, image © Steve Morgan / Wikipedia

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