From climate change to violent nationalist threats, the world is in danger. According to Bill Clinton, our salvation boils down to simple math.

Delivering opening remarks to the executives and government leaders packed into the Plaza Hotel ballroom at the Bloomberg Global Business Forum, the 42nd president of the United States called the audience to action, saying that “the most important thing is whether you believe that social strength, economic performance, and political power flow from division or multiplication, from subtraction or addition.”

“You’re all here because, in one way or another, you intuitively know this. You believe that multiplication is a superior strategy to division. You believe that addition is the superior strategy to subtraction in economics, social inclusion and politics. You believe that there are severe limits on the ability of rising separatist tribalism to solve the problems that [threaten] the opportunities of the modern world.”

Separatist tribalism. He used the phrase multiple times throughout his speech at the forum, which is serving as the successor to the annual meeting of the Clinton Global Initiative, the latter of which was held for the last time in 2016.

Clinton said that separatist tribalism is evident everywhere from the expulsion of the Rohingya in Myanmar, to the estimated 11 million refugees who have fled their homes in Syria since the outbreak of civil war, to the pressures on Jordan and Lebanon regarding their policies in Yemen, and the economic and political crisis rocking Venezuela.

“All of this everywhere is about whether we should share power or grab it, and whether social inclusion is better than domination,” he said.

Resolving and dismantling separatist systems “is the great debate of our time,” Clinton argued, noting that their rise now holds implications for the futures of the United Nations, the European Union, and the United States.

His charge: Fight separatist tribalism by prioritizing inclusion and engaging in cooperation.

Driving the point home, Clinton summarized a central argument presented in American entomologist and biologist Edward O. Wilson’s The Social Conquest of Earth:

“The great E.O. Wilson, who is now almost 90 … says that of all the species that have ever lived on planet Earth, including the 4 million still around today, with 2 million more probably not yet identified, the most successful living species has been humans—closely followed by ants, termites and bees. And he said that’s because we are the best cooperators. And we get the nod ahead of the ants, the termites and the bees because we have consciousness and a conscience. But they must be employed in the service of that cooperation.”

He suggested there exists a special responsibility for those in the audience—including heads of state, philanthropists, and executives from companies that, put together, would be the fourth-largest economy in the world, just after Japan.

Life “has been good to us and to a lot of people we know,” Clinton said. “We’re also quite well aware that a lot of people feel left out, left behind … and are very much in need of a handout to be part of the future that we now take for granted.”

Successful cooperation, he said, depends on “first believing that we can and must every day expand the definition of ‘us’ [and] shrink the definition of ‘them’—and we shouldn’t have to have an earthquake or a hurricane to know that that is what we’re about.”