What makes people change their minds? About the really hard stuff.

Covering the Israeli-Palestinian conflict for the past three years, I've often wondered if people here ever do.

This conflict is frequently described as "intractable," with neither side willing to give up their historical perspective or their entrenched positions to end it. And it does not take many interviews to hear repetitions of the same sweeping narrative repeated on each side. Palestinians from different places cite the same historical events to back their views. Israelis who have never met each other use similar turns of phrase.

"People have a lot of [psychological] resources invested in what they believe about the conflict," says Thomas Zeitzoff, a political scientist at American University in Washington, D.C., who has researched Israeli and Palestinian attitudes.

He says the high political stakes and emotional involvement make it hard for Israelis and Palestinians to change their minds.

But there have been certain shifts – in public opinion and in individual beliefs - during the 68 years of Israel's existence and almost half-century of the Israeli military control over Palestinian territories.

Why? Experts list a range of influences that – to varying degrees – can move or even flip deeply held views.

"You can point to major events, either in the world or people's lives, changes in their social context, as well as changes in the kind of messages they get from politicians and other elite sources," says Brendan Nyhan, an assistant professor at Dartmouth College who researches politics and misperceptions.

Other factors include repeated exposure to a new idea, whatever the source, scientific research, and direct personal experience.

Four people – two Israeli and two Palestinian – told me their stories of personal, radical belief change related to the conflict. They not only changed their minds, but, a higher hurdle, their behavior.

Here are some triggers that led these people to see the world differently than they had before, even in the midst of a larger impasse.

Time With The Enemy

Many groups supporting co-existence advocate for exposure to the other side. Knowledge develops empathy, they say, which can broaden an individual's perspective as well as pique curiosity.

Maayan Poleg is a Middle East program director for the group Seeds of Peace, which brings Palestinian and Israeli teens together for summer camp in Maine. She says the group does not advocate a particular political position and is not directly aiming to change minds.

But time together, deliberately discussing the conflict, humanizes the enemy, she says, and helps participants question their assumptions, as well as navigate the onslaught of opinions from politicians, family and media to clarify their individual beliefs.

"They become open to accepting the fact that what they know as truth is a narrative. That's a huge step," Poleg said. "People spend a lot of time defending a specific fact. And it takes them a long time to understand that their fact is actually a narrative. It doesn't mean that it's wrong. It just means that there's another way to view it."

Palestinians and Israelis used to interact with some regularity, often in the workplace or the marketplace. But over the past 15 years, they have been increasingly separated physically. They now spend very little time together.

But one Palestinian who went from throwing stones at Israeli soldiers to teaching non-violence says he began to change his mind about violence while in an Israeli prison. While behind bars, he learned Hebrew, saw his first movie about the Holocaust, and got to know Israeli prison guards.

"It's a process," says Bassam Aramin, who became one of the co-founders of Combatants for Peace, a group of former Israeli soldiers and Palestinian ex-militants. "You never wake up in the morning and say, 'Oh my God, we are wrong. The Israelis are right. I give up fighting.'"

He remembers the first time he and other ex-combatants – Israeli and Palestinian - sat down together. He was scared.

"We don't trust them. I think they're from the Israeli intelligence. Maybe they are coming to arrest us," Aramin recalls.

He saw fear in the eyes of the Israeli men who sat down with him.

"It's the first time they're coming to meet a Palestinian terrorist. And they have this fear of maybe one of us will kidnap them and kill them."

Trust did build trust over time and many conversations. They built an organization that teaches empathy and understanding.

But empathy is also vulnerable to a change of heart.

Repeat Experiences

Many Israelis and Palestinians reached out to each other eagerly after leaders signed their first-ever peace plan back in 1993.

People were hopeful, and more open than ever to the idea they could live together peacefully, says Palestinian sociologist Nader Said.

"It was highly euphoric and highly exciting times," he remembers.

But that peace deal, the Oslo Accords, did not deliver on its promise. Violence returned with a vengeance when the second Palestinian uprising, or intifada, broke out in September 2000.

Said, who has polled Palestinians since the mid-1990s, says by then Palestinian support for co-existence had already begun to fall, as people grew disillusioned by the gap between expectations and reality.

"While they felt [Israeli] settlement activity would decline, settlement activity has increased," he says. "They felt maybe they'll have more access to Jerusalem, they have less access now."

Palestinian Abla Masrujeh is part of this societal shift. Now 54, she invested her time, money and reputation in joint projects with Israelis in the 1990s. She organized Israeli visits to her hometown of Nablus, in the West Bank, where they shared meals and visited Palestinian homes. She helped present a Tel Aviv exhibition of handcrafts done by women from both sides.

But when violence broke out once again, she felt her new Israeli friends did not understand her experiences as Israeli soldiers swept through the West Bank, or her point of view.

"All this made me rethink my position and my opinion of Israelis," Masrujeh says.

Israelis went through the same reversal of hope, says pollster Tamar Hermann.

"The repeated failures in achieving something tangible, and then the huge waves of terror, this made people think maybe it's not workable," she says. "People started to doubt whether the cognitive change which opened the door for the two-state solution was justifiable."

Many Israelis cite repeated suicide bombings, in cafes and on buses during the second intifada, from 2000 to 2005, as the beginning of a national shift in attitudes toward Palestinians.

American social psychologist Jay Van Bavel says accumulated experience often leads to change.

"Like a rat pressing a lever. If it gets a pellet, it will press the lever again. People are the same way," he says.

A Personal Search For Meaning

Over a decade, Israeli Tamar Asraf's mind and lifestyle turned 180 degrees around. She describes the process not as repetitive feedback, but as digging deeper.

Once secular and opposed to Israel's West Bank settlements as an obstacle to peace, Asraf is now religious and a spokesperson for Eli, a growing settlement in the central West Bank.

"It works like this. You get more connected to yourself, you get more connected to your private roots, then you get more connected to your national roots," Asraf says of her journey.

Exposed to religious Jews during her army service, Asraf began to feel her secular upbringing left huge gaps. When she began to study Judaism, her sense of connection to biblical places in the West Bank grew, trumping Palestinian claims to the same land.

Israel's political power base has shifted to the right over the past two decades, says Avi Dgani, an Israeli expert in mapping social and political dynamics.

But even though identity politics, magnified by frequent violence and international attention, play a large role in the Israeli-Palestinian conflict, Dgani says big personal swings such as the one Asraf experienced aren't all that common.

That's because many people don't deeply question their personal beliefs, or, subsequently, their politics, Dgani says. He cites last year's re-election of Prime Minister Benjamin Netanyahu as an example.

A third of Netanyahu backers chose him simply because "me and my father and my forefather, we always voted right," Dgani says.

Birds Of A Feather

Once people change their minds, one of the most powerful ways to maintain that new belief is to find new friends who share it.

Asraf moved to a settlement because the people there followed the same religious practices she had recently adopted. Once there, she started voting for right-wing leaders, as do most of her neighbors.

Another Israeli, Noam Chayut, shifted to the left politically. He says small jolts shook his beliefs briefly along the way, but real change took off when he found like-minded people.

Chayut wrote a book, The Girl Who Stole My Holocaust, about his change from Zionist soldier to co-founder of Breaking the Silence, an organization of former soldiers who share anonymous stories critical of Israel's military occupation of the West Bank.

Time and a great deal of reflection were key to Chayut's realization that his core beliefs had changed.

"Soldiers get orders, they obey," he says. "You just do things. But reflecting on it, I did things that were close to my moral boundary."

People can be pushed to change their minds when they sense a clash between their beliefs and actions has become too strong.

But change is hard because people protect themselves against internal dissonance, especially in situations as emotionally and politically laden as this conflict, says Thomas Zeitzoff, the American political scientist who has studied how narratives can change here.

"We think people engage in what psychologists would call 'motivated cognition,'" says Zeitzoff. "To avoid things that may threaten our own view of selves or others, maybe motivated in a benign way to remember certain facts more than others, and selectively ignore things that contradict beliefs."

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