News of a local Iraqi man who absorbed the brunt of a suicide bombing by hugging the terrorist spread across social media over the weekend. The attack outside a Shiite shrine still killed at least 40 people, but it could have been hundreds more. On Twitter, people hailed the man as a hero.

But the story of Najih Shaker Al-Baldawi’s sacrifice was never independently verified outside of one Arab news source, and most major news organizations did not run the story because there were questions about whether it actually happened as described. But whether it was true didn’t seem to matter online. People wanted to believe it; they needed to grasp onto this example of heroism to sustain their resolve.

At a time when the world seems as bleak as ever — as international and domestic tensions deepen rifts and heighten anxieties — such acts of selflessness in defense of another person or of an ideal become evidence that good people still exist.

“It’s easy to lose hope. I worry right now in the media there’s a certain amount of hopelessness, that we’ll not be able to bridge the gap,” said Zeno Franco, a professor at the Medical College of Wisconsin who studies heroism. “I think people want to latch on to the hero story because it reminds them that achieving this highest level of humanity is possible even in the most inauspicious circumstances.”

While the idea of heroes is as old as Greek mythology — and has been immortalized by cape-wearing characters with super powers — what makes someone a hero in real life is sometimes overstated.

The descriptor, “hero,” is bandied about a lot these days to describe just about any action that is out of the ordinary. Actress Carol Burnett was once regarded in a news headline  as a “hero” for wearing fuzzy slippers on the red carpet to the Screen Actor’s Guild awards. An athlete might be labeled a hero for a game-winning play. A co-worker might be a hero for bringing a tired colleague a midafternoon coffee.

But in its purest form, the term is reserved for any person who takes an action outside the norm that is self-sacrificing. The principal who died pushing children out of the way of a moving bus. The father who jumped on a suicide bomber in front of his young daughter to save hundreds. The passengers of Flight 93 who downed the jetliner headed for the U.S. Capitol. These are heroes. Indisputably.

Through his extensive research on the topic of heroes, Scott Allison, University of Richmond psychology professor, has identified eight distinct traits of heroes: Smart, strong, resilient, reliable, selfless, caring, charismatic, inspiring. While our most revered historical heroes possess all of these, like the Rev. Martin Luther King  Jr., it is possible to be considered a hero with only a few, he said.

And then there is the gray area. Joseph Campbell, a midcentury researcher on the topic of heroism, described one of the objectives of heroism as “supporting an idea.” That, some argue, leaves the label open to anyone who has a cause, regardless of whether it is deemed morally right.

“Heroism is in the eye of the beholder,” Allison said. “One person’s hero is another person’s villain. One person’s freedom fighter is another person’s terrorist. It’s very subjective.”

“When we ask people to list the traits of heroes, four of those eight also apply to villains, which makes the distinction a fine line,” he added. “There are antiheroes who are smart and strong and charismatic … that describes the Joker in Batman. So who is the hero?”

But Ari Kohen, a political-science professor at the University of Nebraska-Lincoln who wrote the book “Untangling Heroism,” says it’s a person’s actions, not a specific set of characteristics, that defines heroism. Often heroism that is celebrated is an action by average people who responded to a problem in an extraordinary way that put themselves at some kind of physical, social or professional risk. Less often are people lifelong heroes like Mahatma Gandhi or Nelson Mandela.

The spontaneous heroes, like the ones who shield another during a mass shooting, often force us to reevaluate our own priorities. Would we be able to do the same in a split-second? Then there’s more thought-out, prolonged heroism, like people who hid Jewish families during the Holocaust, or people who are whistleblowers exposing government or corporate wrongs. Unlike those who make a swift decision in a crisis (or simply react), the latter have the time to weigh  the pros and cons, but continue anyway.

Franco said it’s this group of heroes that is lacking today, especially in the current breakdown between law enforcement and the African American community.

“Crises create a call for heroes to step forward. We don’t have a unifying voice to find ways to heal the problems we’re encountering right now. I don’t see that. The situation is calling for someone to step forward into that space,” he said. “I see both camps entrenching and trying to push their own view forward and not reaching out and looking deeply at the realities and experiences of the other groups.”

To be a hero in this moment, “it’s going to take someone who is willing to risk a lot,” Franco said. “Their message is not going to be comfortable.”

Because heroism of all kinds is so often seen in the actions of ordinary people, Kohen believes it can be taught. He’s collaborated with Matt Langdon, who runs the Hero Construction Company, which trains children on what it means to be heroic. They teach that the opposite of a hero is not a villain, it’s the bystander. The goal is to show kids that they all have the capacity to be heroes.

Kohen said that’s really the reason people turn to heroism stories during hard times — because it is a reminder that even in the midst of something bad, there is good. It not only makes people feel better about humanity, he said, but it provides something to aspire to.

“It should say to you, ‘You can do something too.’ Anybody can be a helper. It’s not something you have to be born to do,” he said. “That’s what these hero stories show us. All of these people are regular people, they are regular people doing extraordinary things. The message should be you’re just like them.”

Read more about heroes:

Theirs was a 25-year romance. Then the love of her life took a bullet to save a stranger.

This 77-year-old hero was stabbed trying to save slain British lawmaker

In the midst of the Brussels airport attacks, this worker started saving people

‘I Got You:’ San Bernardino victim shielded female co-worker during shooting, saving her life

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