What can kindness do for you? Give you a warm glow perhaps, or a feeling of well-being? While that may be true, scientists and academics at a new research centre say it can do much more - it can extend your life.
The staff at UCLA's Bedari Kindness institute are ready for the jokes.
"We look at the scientific point of view. We aren't sitting around in circles, holding hands. We're talking about the psychology, the biology, of positive social interactions," says Daniel Fessler, the institute's inaugural director.
The notion of kindness has made headlines recently.
It was a key part of former president Barack Obama's eulogy of veteran US Democrat Elijah Cummings, following his death last month.
"Being a strong man includes being kind. There's nothing weak about kindness and compassion," he said. "There's nothing weak about looking out for others. You're not a sucker to have integrity and to treat others with respect."
And then there was Ellen DeGeneres calling for kindness when speaking about her surprising to some friendship with George W Bush: "When I say, 'Be kind to one another,' I don't mean only the people that think the same way that you do. I mean be kind to everyone. It doesn't matter.'"
Ahead of World Kindness Day this week, what does it actually mean to be kind - and why is it important?
This is what the experts want to examine. And they are deadly serious about it. After all, it could be a matter of life and death, they say.
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Mr Fessler's work has looked at how people can be motivated to be kind simply by witnessing acts of kindness - and working out who is affected by this "contagious kindness".
"I think it's fair to say we live in an unkind age right now," he says. "Both domestically in the United States and around the world, what we are seeing is increasing conflict between individuals who hold different political views or belong to different religions."
Kindness, he says, is "the thoughts, feelings and beliefs associated with actions intending to benefit others, where benefiting others is an end in itself, not a means to an end".
And unkindness, on the other hand, is "intolerant beliefs, the lack of valuation of others' welfare".
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It's something familiar to anyone who's experienced trolling on social media.
While the practice is "nothing new", Mr Fessler says "people are more likely to be aggressive, less likely to value others' concerns and welfare, the more anonymous they are".
The institute was founded thanks to a $20m (£16m) grant from the Bedari Foundation, set up by philanthropists Jennifer and Matthew Harris.
Based in UCLA's social sciences department, it aims to help both members of the public and also to inspire leaders.
Mr Harris says research was needed "to understand why kindness can be so scarce in this modern world" and to "bridge the divide between science and spirituality".
Some of the projects at the institute include:
Anthropologists examining how kindness spreads between people
Sociologists analysing how those who behave unkindly could be persuaded to be kind
Psychologists researching how kindness can improve mood and reduce depression symptoms