-This article originally appeared at The Chronicle of Higher Education.

For the first time in earth’s long history, human activities threaten not just local ecosystems but the global environment through climate change, ocean acidification, and other urgent problems. We have so much impact on the planet today that some scientists argue that we have crossed into a new geological period — the Anthropocene, the age of humans.

For many on the left, the Anthropocene is reason to call into question the economic policies and technological advances that have enabled human society to flourish over the past century. To save the earth, some argue, we must end economic growth, give up on our most powerful innovations, and learn to live with much less.

Earth is screwed, and our insatiable growth economy is to blame, declares Naomi Klein in her international best seller This Changes Everything: Capitalism vs. the Climate (Simon & Schuster, 2014), the highest-profile example of this argument to date. “Only mass movements can save us now,” she writes. In order to avoid certain catastrophe, we need “profound and radical economic transformation” that upends our fossil-fuel dominated system of energy and food production.

Klein and intellectual confederates like the author Bill McKibben urge an international shift to small-scale economies powered by community-owned solar panels and wind turbines, supplied by local organic farms, and connected by free public transportation. In this future, countries would de-emphasize economic growth and maximize well-being through minimum consumption, pursuing an egalitarian “good life,” all with the goal of achieving a new harmony with nature.

But for others on the left, halting the many societal gains we have achieved through technological innovation rules out the best tools we have for combating climate change, protecting nature, and helping people.

For these self-described “ecomodernists,” the urgent environmental problems we face are reason for more modernization, not less. “Knowledge and technology, applied with wisdom, might allow for a good, or even great, Anthropocene,” 18 academics and intellectuals argued last month in an “Ecomodernist Manifesto” outlining their views.

Hope for a better future, they contend, starts with advanced technologies that intensify rather than weaken our mastery of nature. High-tech crops, advanced nuclear power, carbon capture and storage, aquaculture, desalination, and high-efficiency solar panels all have the potential to not only reduce human demands on the environment but also spark the economic growth needed to lift people out of extreme poverty.

These advances will enable more people to live in bigger cities that are powered and fed more efficiently. People in cities also tend to have fewer children, slowing population growth. From this perspective, technological advances and urbanization will free up more space on the planet for nature.

Yet to achieve this future, ecomodernists warn that we have put too much faith in carbon pricing, social-impact investing, venture capital, Silicon Valley, and other market-based “neoliberal” mechanisms to spur technological innovation and social change. We need to instead focus more intensively on understanding how technological advances happen and the role of government planning and spending (rather than the market) as the main driver of innovation and societal change.

Once there are technologies available that make meaningful action on climate change and other problems cost less, ecomodernists predict, much of the political argument over scientific uncertainty will diminish.

Under those conditions, it will be easier to gain political cooperation from across the ideological spectrum and from developing countries. National leaders and their constituents are far more likely to spare nature because it is no longer needed to meet their economic goals than they are for any ideological or moral reasons.

“An Ecomodernist Manifesto” is the brainchild of Michael Shellenberger and Ted Nordhaus, co-founders of the Oakland, Calif.-based think tank the Breakthrough Institute. A decade ago, in an essay titled “The Death of Environmentalism,” they were among the first intellectuals on the left to question the politics of limits that has long defined the environmental movement.

In the years since, with support from the Nathan Cummings Foundation (which has also supported my work), the institute has played a lead role in forging an international network of academics and intellectuals who share the goal, as the institute’s website puts it, of “challenging conventional progressive and environmental wisdom in service of creating a relevant and powerful new politics.”

Examples of other ecomodernist thinkers, all co-authors of the recent manifesto, include the University of Colorado at Boulder political scientist Roger Pielke Jr., the Harvard University applied physicist David Keith, the Columbia University geographer Ruth DeFries, the Stanford University historian Martin W. Lewis, the University of Maryland at Baltimore geographer Erle C. Ellis, the futurist Stewart Brand, the filmmaker Robert Stone, the writer Mark Lynas, and the philanthropists Rachel Pritzker and Peter Teague.

For these ecomodernists, progress requires respectful engagement with a diversity of voices and ideas. “Too often discussions about the environment have been dominated by the extremes, and plagued by dogmatism, which in turn fuels intolerance,” they write.

Yet their call for respectful debate and critical reflection has been met with intense hostility by many of their counterparts on the left. At, the blogger Joseph Romm dismissed the manifesto as an Orwellian time waster and encouraged his readers to skip any discussion of its ideas. In her book, Klein writes that ecomodernists are either “dishonest or delusional,” as they advocate a “doubling down on exactly the kind of reckless, short-term thinking that got us into this mess.”

In a recent essay at Aeon magazine, the Duke University law professor Jedediah S. Purdy accused ecomodernists of being nothing more than “branding opportunists,” sloshing “around old plonk in an ostentatiously shiny bottle,” all in an effort to win speaking and consulting fees. In a blog post last year, the philosopher Clive Hamilton, of Charles Sturt University, in Australia, declared that by promoting the possibility of the “good Anthropocene,” ecomodernists are “unscientific and live in a fantasy world of their own construction.” In Earth Island Journal last month, he dismissed the recent manifesto as “detached and dreamy, and blind to the hard truths of political combat.”

On the road to managing the many threats we face in the Anthropocene, grass-roots activism and political reforms are important, as is the quest for a more advanced arsenal of technological options and a reconsideration of our economic goals. But so too is investment in our capacity to learn, discuss, question, and disagree in ways that constructively engage with uncomfortable ideas.

Yet most academics and journalists avoid challenging the powerful forms of groupthink that have derailed our efforts to combat climate change. In this regard, attacks on those who question cherished assumptions have had a powerful chilling effect. We therefore depend on risk-taking intellectuals like the ecomodernists to lead the way, identifying the flaws in conventional wisdom, and offering alternative ways of thinking and talking about our environmental future.

In such roles, argued Michel Foucault, the function of the intellectual is to “question over and over again what is postulated as self-evident, to disturb people’s mental habits, the way they do and think things, to dissipate what is familiar and accepted, to re-examine rules and institutions.”

Conversely, as the sociologist Amitai Etzioni has warned, in the absence of risk-taking intellectuals challenging assumptions, those working on complex problems like climate change may “be lacking in reality testing, be slower in adapting … policies and viewpoints to external as well as domestic changes, and be more ‘ideological.’”

Reading Klein, it is clear that she is not confident that the mass movement she calls for and the deep structural reforms that “change everything” are achievable. Instead, like radical intellectuals of movements past, her utopian vision serves an important political function, creating space for the more pragmatic, less revolutionary ideas of the ecomodernists and others.

With the 2016 U.S. elections on the horizon, ecomodernists are “providing arguments for people in the middle to hold on to so they can have some kind of environmental vision,” Paul Robbins, director of the Nelson Institute for Environmental Studies at the University of Wisconsin at Madison, told Slate. “You’ve got to have some kind of position, and they’re offering them something to jump at. It’s not like they’re going to jump on Naomi Klein’s bandwagon.”

In navigating a path forward on our tough, new planet, our success depends on constructively grappling with diverse perspectives. Through this approach we can hold our own convictions and opinions more lightly, pursuing the very best of the many ideas available.