When I first heard about Half-Earth — the remarkable vision to save all life from extinction by setting aside half of the Earth's land from humans — it amazed me with its boldness. Biologist E.O. Wilson's book by the same title describes this big idea — half of Earth for us humans, half for everything else.

I read about Half-Earth in a 2014 article in Scientific American and learned about Wilson's partnership with M.C. Davis, a multimillionaire philanthropist working to revive the "Piney Woods" ecosystem in the Southeast. With Wilson's expertise and Davis' resources, they acquired a swath of land to make a safe corridor for the Florida panther to travel and reproduce.

Wilson's book lays out a map of more set-asides for preserving the natural spaces where biodiversity can still flourish. A 2017 update reports — to many scientists' and politicians' surprise — that the plan could work.

If only more of us will get on board.

Half-Earth's success (meaning life does not go extinct) depends on a bold set-aside model. It asks the rest of us to up our game by clustering more closely together and increasing the density of our cities. This will make space for the rest of life to have a fighting chance.

This big idea bumps up against the life I live in the 15th-largest media market in the U.S., the cities of Minneapolis and St. Paul. Both cities are drafting their futuristic plans for the next phase of development. The plans are known by the date they are aiming toward: 2040.

Both cities are growing in population. Both cities suffer from historic injustices and segregation. Both lack affordable housing. Both plans call for taller buildings, more housing options, more options for transit with less parking. Both try to imagine what life will be like in 2040.

Much controversy has erupted. I'm astonished by the venom such planning documents produce. I read that one of the main planners for Minneapolis was told at a community meeting that she is "the most hated person in the city." She responded, "I don't take it personally and I practice radical compassion."

I wonder what such compassion looks like, as the plan goes through another revision and attempts to respond to the anger.

The stakes are high. We must repair and restore historic inequities that run deep. Our state is projected to be one of the most affected by climate changes. We disagree about how to move forward.

I've spent a lot of my time with other earnest, knowledgeable, engaged people working together on these plans. In the parts of the cities where I've participated in drafting plans (the Towerside Innovation District that straddles Prospect Park and St. Anthony Park, located on the 50-yard line of the two cities), we're asking (we would like to do more than ask!) that all new development in the area take to heart the task of implementing much more ambitious goals to address climate, resilience, equity and health. To adopt systems for district energy, district water, walkable and bikeable streets and trails, and, yes, denser housing with maker and innovation spaces built in for a 21st-Century workforce.

Then I read angry posts about the plans by many friends on social media and wonder what they read that makes them so angry. I wish more of them were angry about historic inequities. I wish more of them were focused on trading their vision for Wilson's vision.

And I wonder, are we fundamentally afraid of change? Do we fear loss? The losses of a way of life we've come to expect instead of noting the invisible losses of creatures who move along the forest floor unnoticed, who provide food for the next species up the line. We may notice fewer birds singing in the mornings. We don't notice the emptying of the oceans and forests of critters we forget even exist.

E.O. Wilson puts it well: "Battles are where the fun is, and where the most rapid advances are made."

Our way forward depends on the relationship between the plans, the planners, the developers, the experts and residents. We've got more to fight through as we do our best to make 2040 plans for our future cities.

Reading the Half-Earth Project website and its mission speaks to my sense of civic pull: "Engage people to participate broadly in the transcendent goal to conserve Half-Earth." Transcendent. Moral. Our Spiritual Task.

Because of Half-Earth, my wish is for us to raise our sights, traveling through our imaginations, to see our cities and ourselves and our crucial role in saving us from extinction. Yes, the stakes are that high.

Catherine Reid Day, of St. Paul, serves on the board of the Towerside Innovation District and chairs the board of the Creative Enterprise Zone. She's the founder of Storyslices, a strategic communications and coaching company working at the intersection of story and purpose.