Laboratory assistants have to do all sorts of terrible, embarrassing things, but surely this is among the silliest: Enter a bar in Grenoble, France. Identify people who look moderately drunk. Walk up to them, tap them on the shoulder, and say something along the lines of, "Uh, hey, this is awkward, but, would you be interested in answering some questions about philosophy?"

Such was the fate of some poor, unnamed graduate student who did "most of the recruitment" for a recent study about the relationship between alcohol consumption and ethical decision-making. In two separate experiments, researchers presented bar-goers with a questionnaire about philosophy and their state of mind; a total of 102 men and women took part. ("One participant was excluded from the study because he did not follow the instructions properly," the researchers note—a remarkably low number, considering that all their subjects were drunk.) After the participants filled out the survey, they took a Blood Alcohol Content test so that researchers could measure how intoxicated they were.

The researchers asked participants to give their opinion on two of philosophers' favorite quandaries: the so-called trolley problem and its cousin, the footbridge problem. In the first, people must choose whether they would flip a switch to divert a runaway trolley, killing one person but sparing five others; the second asks about pushing someone off a bridge for the same purpose. "A drawing accompanied the text of each vignette in order to facilitate understanding of the story," perhaps in case the subjects were too drunk to read.

"The idea was to look more at the more moral and ethical implications of how alcohol might affect decision-making," said Aaron Duke, one of the researchers.* His team found a correlation between each subject's level of intoxication and his or her willingness to flip the switch or push the person—the drunker the subject, the more willing he or she was to kill one hypothetical person for the sake of the hypothetical many. This choice follows the logic of utilitarianism: More good is done by saving five people than harm is done by killing one.

This "really undermines the notion that utilitarian preferences are merely the result of more deliberation," said Duke, who also co-authored a paper on the study, charmingly titled, "The drunk utilitarian: Blood alcohol concentration predicts utilitarian responses in moral dilemmas."

There's a fabulous irony in the idea that drunk people are emotionally steeled rationalists who are willing to do whatever it takes to save lives. But Duke and his research partner, Laurent Bègue, aren't necessarily arguing that drunk people are ace philosophers and logicians; it's more that their findings challenge common assumptions about how people make decisions.

"There's this argument that utilitarian ethics are correct; they're associated with people who are less emotional. Our finding was that this may not necessarily be the case," Duke said.

One explanation he offered is that drunk people might be less sensitive to what happens to the guy who's on the wrong side of the hypothetical tracks or bridge—"it seems like a reasonable explanation that the effects of alcohol would decrease emotional sensitivity toward someone else's pain." In general, he said, the study reinforces the complexity of figuring out why people make the choices they do. "Ethical decision-making is influenced by things like substances—it shifts the ethical frame by which we view the world."

Duke also recognized that the implications of the study are limited, especially because the sample size is so small. Plus, the questions themselves have flaws.

"To be honest, with the trolley problem in general, there is going to be a range of seriousness with which people view it, because it's kind of a ridiculous premise," said Duke. "I don't know that inebriated people would take it any less seriously. But alcohol can make it almost more simplistic—they may be less likely to question some of the assumptions upon which the task is based."

In other words, drunk people are more willing to "just go with it" when a random graduate student asks them to participate in a thought experiment about killing people. Utilitarian or no, the inebriated may be the philosophy researcher's dream.

* This post originally stated that the researcher's name is Aaron Blake. We regret the error.
