College students who hit campus after 2000 have empathy levels that are 40% lower than those who came before them, according to a stunning new study presented at the annual meeting of the Association for Psychological Science by University of Michigan researchers. It includes data from over 14,000 students.

Although we argue in Born for Love: Why Empathy Is Essential--and Endangered that modern child-rearing practices are putting empathy at risk, this is the largest study presented so far to quantify the decline.

Previous research done by psychologist Jean Twenge had measured what she labeled a "narcissism epidemic," with more students showing selfish qualities and with increases in traits that can lead to a diagnosis of . That is a condition in which people are so self-involved that other people are no more than objects to reflect their glory.

But I was less than convinced by that data because some of the measures of --statements like "I am a special person," --might reflect a lifetime spent in classrooms aimed at raising rather than a true increase in self-centeredness.

The survey on empathy used in this study--which you can take for yourself here--however, is another matter. While it so obviously measures empathy that you could easily game it to make yourself look kinder and nicer, the fact that today's college students don't even feel compelled to do that suggests that the study is measuring something real. If young people don't even care about seeming uncaring, something is seriously wrong. Another survey in the research found that people also think that others around them are less compassionate.

Why might today's students be less than their elders? One of the culprits we identify in Born for Love is the way that they spent most of their time early in life. Today's kids play outdoors much less--and they spend far less time in unstructured activity with others than prior generations.

Without unstructured free time with playmates, children simply don't get to know each other very well. And you can't learn to connect and care if you don't practice these things Free play declined by at least a third between 1981 and 2003--right when the kids who hit college in 2000 and later were growing up.

Worse, much of the time that used to be spent playing outdoors is now spent in front of screens. Television, obviously cannot teach empathy. Even nonviolent kids' TV, research finds, is filled with indirect and linked to increased real-world . Though social media is an improvement on passive TV viewing and can sometimes aid real friendships, it is still less rich than face to face interaction. This is especially important for the youngest children whose brains are absorbing social information that will shape the way they connect for the rest of their lives.

Another factor is the "self esteem movement" and its pernicious notion that "you can't love anyone else until you love yourself." Today's kids grew up with parents who were taught by therapists and groups attended by millions that caring too much for other people or having your tied to theirs was "co dependence,"--and that people should be able to be happy on their own, needing no one.

In reality, we need each other to be both mentally and physically healthy. Solitary confinement, in fact, is one of the most experiences someone can undergo: this wouldn't be true if most people were happy without social contact. Normal people kept in complete isolation can become in as little as a few days.

Further, unless you have been loved well from infancy, loving others is difficult--children who are to early are those who find others to care for them to make up for abusive or neglectful caregivers. If the only love they get is from a therapist or teacher who tells them to love themselves before trying to make other connections, they are extremely unlikely to recover.

Perhaps an even larger factor is the merging of the left's "do your own thing" individualism with the right's glorification of brutal and unfettered markets. You wind up with a society that teaches kids that "you're on your own" and that helping others is for suckers. A country where the mystical new age "Secret" is that the rich deserve their wealth and got it by being positive and good--while the poor, too, get what's coming to them because they didn't try hard enough.

At the same time, deregulation and reduced taxes on the wealthy from Reagan onwards produced massive growth in economic inequality, which is probably also a critical part of empathy's decline. Empathy requires an ability to understand others--it's easiest to do this when you spend time them regularly and know how to read them.

Economic inequality, however, by radically separating the rich from the poor and shrinking the middle class, literally physically isolates us from each other and provides few opportunities for connection or understanding. If you spend your time in limos and gated communities and first class, you aren't likely ever to meet poor people who aren't there to serve you; outside that context, you won't know how to relate to them.

And then, if you know nothing about someone's real situation, it's easy to caricature it as being defined by bad choices and laziness, rather than understand the constraints and limits the economy itself imposes. Seeing yourself doing so well and others doing poorly tends to bolster ideas that "you deserve your wealth," simply because otherwise becomes uncomfortable, even unbearable.

In reality, self esteem doesn't come from thinking positive or telling yourself that you are special or worthy--though telling kids they are rotten and selfish can surely destroy it. And, sadly, you can be all you like in an economy with 20% unemployment and still not get a job through no fault of your own.

So what can be done about what President Obama as a candidate presciently labeled the "empathy deficit"? The key thing is to recognize the value of relationships and the fact that we are not independent but interdependent. We all need each other. We're actually both happier and healthier if we're kind.

Countries with high economic inequality tend to have high , high corruption, low levels of trust, high infant mortality and lowered life expectancy-- as well as difficulty growing their economies. In contrast, those with lower inequality have higher happiness, greater health, lower crime, better growth and longer life.

And so, if, say, health care for all or better unemployment benefits or higher quality schools means that those lucky enough to have well-paying jobs have to pay higher taxes, well, is that really so terrible?

If we continue to believe that it is, if we continue to split into "us" v. "them," "haves" v. "have nots," the empathy decline will undoubtedly continue and we will face a meaner, nastier world in which ideas about humans being selfish and competitive rather than caring become a self fulfilling prophecy by crushing the tendency toward kindness with which we are all born.

[Cross-posted on HuffingtonPost, Newstilt]