A Harvard-led team is testing whether mutually beneficial cooperation can ease affective polarization at scale.
Rising political animosity is straining democratic life in the United States and beyond. Decades of research suggest hostility can soften when people have meaningful contact across groups under the right conditions — especially when they’re working toward a shared goal.
With support from Templeton World Charity Foundation’s Listening & Learning in a Polarized World, a team led by Joshua Greene and Scott Warren set out to test a practical question: can mutually beneficial cooperation reduce partisan animosity even in an anonymous online setting?
To find out, they created Tango, a live, cooperative quiz game that pairs Democrats and Republicans as teammates.
Across five experiments (N = 4,493), about an hour of gameplay with an outparty partner reduced negative partisanship, increasing warmth, improving perceptions of the other side, and shifting behavior in fairer directions, with effects that could last up to four months. The game also briefly improved democracy-related attitudes and earned high enjoyability ratings, a key ingredient for anything meant to scale.
A lot of bridge-building starts with dialogue. Tango starts with incentives. Instead of asking people to debate in good faith (often a big ask online), Tango makes cooperation the fastest route to success.
As the Harvard Gazette reported when the research was released, Tango pairs Democrats and Republicans on the same teams — so “bipartisanship quickly emerges as a competitive advantage.”
Tango “is not your typical quiz game.” You’re matched with an anonymous partner and collaborate in real time, using chat to coordinate answers. The goal is simple: win together.
On the Tango site, the team emphasizes that this is not an attempt to push everyone toward the middle. The point is experiential: show that “truth isn’t monopolized by any side,” and that people can disagree while still being respectful.
To keep the experience grounded, Tango says it sources questions from “the most reliable available sources,” including scholarly articles, nonpartisan polling, government statistics, nonprofit reports, and reputable journalism.
If you’re curious to try it, the “Let’s Tango” page notes you can sign up and they’ll notify you “when it’s time to connect with a live partner,” plus offers a short explainer video and downloadable instructions.
The results are summarized in Nature Human Behaviour (https://doi.org/10.1038/s41562-025-02225-2). Across five experiments, the authors report that an hour of Tango with an outparty partner reduced negative partisanship, increased self-reported warmth, improved outparty meta-perceptions, and led to more equitable economic allocations with effects persisting up to four months.
The Harvard Gazette story also flags a practical takeaway: the intervention is short, engaging, and measurable. This is a rare combination for depolarization work.
Tango’s “Approach” page describes the broader ambition: dialogue matters, but it often requires a baseline level of respect that many communities feel has eroded. Tango aims to rebuild that baseline by creating a cooperative dynamic first — then introducing controversial topics while keeping the focus on “accepting facts, not reconciling values.”
As the Harvard Gazette reports, the team is also customizing Tango for different national settings as polarization rises globally. Pilot testing is underway in Israel, with question sets for India and Northern Ireland in the works. Greene emphasizes that constructive dialogue remains essential in divided societies — but it depends on something even more basic: “that basic sense of mutual respect and openness — of thinking ‘this person is on my team.’”
“So, what we’re trying to do with this game is expand the definition of ‘us,’” he adds. “It’s less like two smart humans having a debate about immigration and more like two chimps picking bugs out of each other’s fur.”
Tango is also positioning itself as a tool for organizations — especially higher education, where it can be integrated into orientation, classrooms, and campus initiatives, and for companies looking to build cohesion and respect. Tango also highlights early reach: it says the game “has been played by thousands across the US.”
