In my last column, I wrote about a high school buddy, Kevin Green, a warm and helpful man who floundered in a tough job market, hurt his back and died at the age of 54. The column was a call for empathy for those who are struggling, but, predictably, scolds complained that Kevin’s problems were of his own making.

Grrrr.

So what do we know about empathy and how to nurture it?First, it seems hard-wired. Even laboratory rats will sometimes free a trapped companion before munching on a food treat.

“Probably the biggest empathy generator is cuteness: paedomorphic features such as large eyes, a large head, and a small lower face,” Steven Pinker, the Harvard psychologist, tells me. “Professional empathy entrepreneurs have long known this, of course, which is why so many charities feature photos of children and why so many conservation organizations feature pandas. Prettier children are more likely to be adopted, and baby-faced defendants get lighter sentences.”

Not much we can do about looks . although criminal defense lawyers try, by having scruffy clients shave and dress up before appearing in court.

There’s also some research suggesting that wealth may impede empathy. One study by psychologists at the University of California at Berkeley finds that drivers of luxury cars are more likely to cut off other motorists and ignore pedestrians at a crosswalk. Likewise, heart rates of wealthier research subjects are less affected when they watch a video of children with cancer.

Granted, skepticism is reasonable any time (mostly liberal) academics reach conclusions that portray the wealthy in a poor light. But these experiments also find a measure of backing in the real world. For example, among Democratic politicians, personal wealth is a predictor of supporting legislation that would increase inequality, according to a journal article last year by Michael W. Kraus and Bennett Callaghan.

Likewise, the wealthiest 20 percent of Americans give significantly less to charity as a fraction of income (1.4 percent) than the poorest 20 percent do (3.5 percent), according to Bureau of Labor Statistics data.

That may be partly because affluence insulates us from need, so that disadvantage becomes theoretical and remote rather than a person in front of us. Wealthy people who live in economically diverse areas are more generous than those who live in exclusively wealthy areas.

Wealth may also turn us inward. Some experiments manipulated research subjects to think of money . such as by having them gaze at a pile of Monopoly money and imagine great wealth . and found that when a person then “accidentally” spilled pencils nearby, those thinking of great wealth were less helpful than those imagining tight budgets and picked up fewer pencils from the floor.

So how do we increase empathy?

Dacher Keltner, who runs the Greater Good Science Center at the University of California at Berkeley, says that having people think about suffering activates the vagus nerve, which is linked to compassion. He also cites evidence that uplifting stories about sacrifice boost empathy, as do various kinds of contemplation . prayer, meditation, yoga.

Keltner says that going out into nature also appears to encourage greater compassion. Feelings of awe, such as those generated by incredible images from space, seem to do the same thing, he says.

Professor Pinker, in his superb book “The Better Angels of Our Nature,” explores whether the spread of affordable fiction and journalism beginning in the 18th century expanded empathy by making it easier for people to imagine themselves in the shoes of others. Researchers have found that reading literary fiction by the likes of Don DeLillo or Alice Munro . but not beach fiction or nonfiction . can promote empathy.

I used to be cynical about student service projects, partly because they seemed so often to be about dressing up a college application, and trips so often involve countries with great beaches. (Everyone wants to help Costa Rica!) Then there was The Washington Post’s report about the Mexican church that was painted six times over the course of a summer by successive waves of visitors.

Yet I’ve come to believe that service trips do open eyes and remind students of their good fortune. In short, they build empathy.

So let’s escape the insulation of our comfort zones. Let’s encourage student service projects and travel to distant countries and to needy areas nearby. Whatever the impact on others, volunteering may at least help the volunteer. Let’s teach Dickens and DeLillo in schools, along with literature that humanizes minority groups and builds understanding.

Above all, let’s remember that compassion and rationality are not effete markers of weakness, but signs of civilization.