You dive to change the channel when that unbearable Sarah McLachlan animal-cruelty ad comes on. But when you hear there’s been an earthquake in South America and thousands are feared dead … you just shrug. You’re colder than that lone, shriveled ice cube in the back of your otherwise empty freezer. You know you should feel sad. Instead, you just feel mildly inconvenienced: What if the earthquake affects coffee production? Your Costa Rican vacay? Don’t worry — you’re not a psychopath, at least not because of this. You simply suffer from what scientists call “emotional innumeracy.”

It turns out that our ability to empathize is seriously limited. A study published by Journal of Experimental Social Psychology shows:

Reading about the deaths of

saddens us no more than the deaths of

The study broke up 173 Duke University students, 44 percent of whom were women, into two groups. Half of the first group of participants were asked how sad they would feel, on a scale of 1 to 9, if they read an article about the deaths of five people; the other half were asked the same question, but regarding the deaths of 10,000. The “forecasters” who got the 10,000-person question predicted greater sadness. A second group, also split in half, actually read these articles and reported on their feelings at the end. There was no difference in emotion between those who had read about five deaths versus 10,000.

This might ring a bell. The results of this study are a sort of cousin to the findings of what you might know as the train-tracks dilemma, conducted in 2011 by Michigan State University researchers. Participants were in a 3-D setting, operating an out-of-control train that, if unstopped, would hit and kill five people. But if the conductor were to switch tracks, she’d kill only one person. Should the conductor intervene? In that study, the opposite seemed to be true: 9 out of 10 participants would kill one to save five — prioritizing the greater number of people over the individual. 

The reason this study seemingly opposes the findings in Journal of Experimental Social Psychology is because we can’t handle numbers that large and make rational or emotional judgments about them, says study author Carlos Navarrete, associate professor of psychology at Michigan State University: “Seeing and feeling those people in front of you changes how you react,” he says. “Our brains are evolved to deal with small numbers, definitely not 10,000. You can make rational choices about killing one to save five but not between 10,000 and five.” And experts say natural evolution is not likely to make us more caring, either. For that to happen, people who sympathized with groups should be more likely to survive and pass on their genes, says George Loewenstein, professor of economics and psychology in the social and decision sciences department at Carnegie Mellon University. ”Nothing suggests that this is an evolutionary trend.” 

Take heart! There may be an antidote for your lack of one. According to the Journal of Experimental Social Psychology study, seeing pictures of death and suffering does provide some empathic perspective. The picture of 1,000 dead bodies, for example, makes the viewer sadder than that of 10 dead bodies. But gruesome imagery can desensitize us and, if there are too many people in the picture, our brain is likely to start seeing them as just dots and lines. In other words, the same “emotional innumeracy.”

Add to this our many other empathy biases like race, sex or cuteness and you’ve got yourself a seriously skewed moral compass. Some argue that we should just stop listening to our heart for direction in the face of vast human suffering. Jesse Prinz, professor of philosophy and director of the Committee for Interdisciplinary Science Studies at the City University of New York, says empathy is “very important for personal relationships,” but points to reason as “essential for allocating resources fairly in a world that is full of moral crises.”

So feel free to have a meltdown over breakups or family dysfunction. But when it comes to pandemics, genocide or famine, don’t trust your gut. You’ll be a better person.

• Michigan State University