Stanford neuroscientist Jamil Zaki's new book, "The War for Kindness: Building empathy in a fractured world," makes a powerful case for kindness and empathy - not only because they make the world a better place, but because they help us, too. I sat down with Zaki to talk about why empathy is endangered and what we can do about it. Our conversation has been edited for clarity and brevity.

Question: You have spent your career researching the neuroscience of empathy. What motivated you to write this book?

Answer: First, empathy seems to be endangered. In one study, the average American college student in 2009 scored as less empathic than 75% of students in 1979. This suggests our care is eroding, but you might not need a study to tell you that. I, like many people, noticed a culture that feels increasingly cruel, callous and disconnected. Second, my own research suggests it does not have to be this way.

Question: Why might empathy be declining?

Answer: People empathize most easily when they can see others' suffering with their own eyes, or when their actions are visible to others. But the modern world has stripped them away. Humans increasingly live in cities and live alone. We see more people than ever but know fewer of them. Rituals that used to bring us into regular contact, ranging from bowling leagues to grocery shopping, have been replaced by more solitary pursuits, often carried out online. The result is our interactions with each other are often thinned out, anonymous and tribal - barren soil for empathy.

Question: Is our loss of empathy irreversible?

Answer: Empathy is a trait in some ways - it certainly has a genetic component. But we can turn our emotions up or down in the moment and practice empathy over time. Researchers have documented several habits, such as lovingkindness meditation, fiction reading and making friends from different social groups, that can expand our capacity for care.

Question: Is having more empathy always a good thing?

Answer: No emotion is always helpful or harmful. Stress feels bad but can energize us to face challenges. Happiness feels good, but at its deep end can turn into mania. The same goes for empathy. There are many cases in which more care is a good thing, but also many in which it can produce exhaustion, burnout and helplessness.

Viewers who are inundated with tragedies develop "news fatigue;" empathic parents worry so much about their kids that they develop signs of cellular aging. In the book, I write about the NICU doctors and nurses who cared for my daughter Alma in her first weeks. They were empathic superheroes, whose willingness to connect at a personal level meant everything for our family.

But that same empathy turns into an occupational hazard. In "caring professions," the most empathic individuals are also most likely to experience symptoms of depression and burnout.

The good news, however, is there is one type of empathy that can actually protect us against burnout.

Vicariously "catching" other people's emotion is what causes overwhelm and burnout. But if you are moved to help people who are suffering without letting yourself be overwhelmed by their pain, you actually benefit from the experience and are protected from burnout.

Psychologists and teachers are working to help people "tune" their empathy away from distress and toward concern using techniques such as meditation, for example.

Question: What can kindness do for a person?

Answer: Our ability to care for, help and cooperate with each other is the cornerstone of human culture and one of the keys of our species' success. Kindness continues to help us at many levels. Helping others boosts individuals' happiness and decreases their stress. Strong social connections even increase longevity in older adults. Empathy strengthens a range of relationships. Individuals with empathic spouses are happier in their marriage; patients of empathic doctors are more satisfied with their care; employees of empathic managers call in sick less often with stress-related illness. Prosocial organizations thrive, too. For instance, empathic teams collaborate more effectively, and businesses that incentivize kindness enjoy greater morale and loyalty.

Question: Has technology had a positive or negative impact on empathy?

Answer: It is common to hear that technology, and especially life online, have taken away our common humanity, and in many ways, that's true. Online interactions often replace live hangouts, and by comparison are thin and bloodless, lacking the nuance and depth of old-fashioned conversation. There's at least some evidence this reduces empathy, especially across group boundaries. Likewise, anonymity allows trolls to practice cruelty without consequences, and public online forums reward outrage and schadenfreude.

It's tempting to blame technology for its ill effects, and many people have. But it is only a tool, and it reshapes human interactions based on what we design and how we use it. The Internet is also an unprecedented empathic opportunity - to deeply see the lives of people around the world, on their own terms, and be seen in return. The way technology affects us in the years to come is up to us.

Question: How has empathy changed you?

Answer: They say "research is 'me' search," and for me that's certainly the case. My parents come from two very different cultures - Pakistan and Peru - and went through a long and difficult divorce during my childhood. I learned, as a survival skill, to connect deeply with both of their perspectives. Empathy saved me, but not because it came easily. My parents' divorce was like an empathy gym, forcing me to work at care and connection. Those skills were the most important I ever learned.

Emma Seppälä is science director of Stanford University's Center for Compassion and Altruism Research and Education, and co-director of the Yale College Well-Being Project at the Yale Center for Emotional Intelligence.