One of the singularly best things the United Nations produces each year is the Human Development Report, a flagship annual publication that tracks and analyzes the state of human progress around the world. What makes the Report so remarkable is that it combines rigorous data analysis with an ever-changing and (for the UN) quite expansive point of view: recent editions have focused on the impact of political polarization on development, how uncertainty affects human wellbeing, and (just this past year) the ways artificial intelligence might shape (or hinder) human progress. (In full disclosure: I serve on an advisory panel for the Report, which is stewarded by the brilliant economist Pedro Conceição.)

The central metric employed in the report is the Human Development Index (HDI), a simple and powerful measure that captures how long we live, how well we’re educated, and how decent our standard of living is. The HDI is not exhaustive, but measuring it consistently over time helped move many policymakers beyond the use of GDP as the sole yardstick of success. And that made a real difference: since the HDI was first introduced in 1990, despite interruptions, disparities, and reversals from things like COVID-19, humanity now, on average, lives longer, receives more years of education, and enjoys higher incomes than we did three decades ago.

Yet the positive trajectory of the HDI tells only part of the story. For far too much of our common progress has been conditioned on the desecration of the natural world, marked by accelerating climate change, ecosystem degradation, biodiversity loss, and widespread pollution. The Earth system is durable and regenerative, and can accommodate some use of its resources, but nothing like what humanity is increasingly doing to the planet. Of the nine planetary systems that make it possible for humanity to flourish on the Earth, we have now pushed six beyond their regenerative limits, imperiling the stability of the biosphere, and ourselves along with it.

There are no happy people on a dead planet. So it’s clear that to guide the development of both thriving societies and a healthy world, we have to measure both the state of nature and the state of humanity together, in ways that are both consistent, rigorous and reflect their complex and diverse interrelationships. 

That’s the argument put forth in a new paper, An Aspirational Approach to Planetary Futures [Nature 642, 889–899 2025] by a team of renowned ecological, planetary and social scientists who explore complementing the HDI with a new measure: the Nature Relationship Index (or NRI), which would track, year by year and country by country, whether we’re building societies in which both people and the larger web of life can thrive.

The authors propose three plain-language dimensions of the nature-human relationship to power the proposed NRI:

  • Nature is thriving and accessible. Are there places, both urban and rural, where people can safely experience nature’s benefits and where wild species can actually live? Think: protected and community-conserved areas that work, thriving urban greenspaces, and restored landscapes you can get to without a multi-day trek.
  • Nature is used with care. Are we meeting human needs in ways that don’t degrade the living world? Think: using energy and materials efficiently; shrinking pollution and waste; producing food on less land with less damage.
  • Nature is safeguarded. Do we back up our good intentions with real legal and financial protections-rules that keep air and water clean, protect species, and hold polluters to account, and budgets sufficient to enforce them?

I love the simplicity and relationality of this compound metric: rather than measuring the state of nature in the abstract, it measures our relationships with it in terms most people value and understand. I would like to see the metric pushed even further, perhaps with a fourth dimension that measures the degree to which nature is understood and valued in societies. (And thus, whether a given relationship between people and nature is likely to be durable.) 

For me, a central test of any combined NRI/HDI index is whether it can help frame effective choices for large countries and blocs that need restorative and regenerative pathways, not just affirm those who are already succeeding. Today, smaller nations, like Costa Rica or Bhutan, have been the clearest exemplars of durable, healthy relationships between people and nature, in large part because their scale, social cohesion, and distinctive political choices have allowed them to do so. Costa Rica’s abolition of its military and reinvestment in education and conservation, and Bhutan’s pursuit of Gross National Happiness with strict environmental protections, stand as almost archetypal cases of “development within ecological limits.” But the record among larger, more complex economies is far more mixed. Some, like the European Union as a bloc, have demonstrated a measure of relative decoupling: they have cut emissions substantially while maintaining economic and social progress. Others, such as China, have made massive gains in human development but at extraordinary environmental cost, only belatedly pivoting to renewable energy and conservation. The United States, meanwhile, has achieved partial decoupling of GDP growth from emissions, but still sustains one of the world’s highest per-capita ecological footprints. What emerges is a pattern in which small nations, with fewer entrenched industrial interests and greater social consensus, can more fully align human and ecological health, while larger nations struggle to reconcile the scale of their consumption with planetary limits.  The question is whether a combined index simply tracks this reality or can help drive change at the superpower/super-bloc level, where a lot of the action must take place. 

To measure the human-nature relationship with rigor and durability also requires bridging a different kind of chasm: the divide between the cultures of human development and Earth-systems science. These two communities often sit side by side at the same tables, but they bring different starting assumptions, languages, and priorities.

The human development community is animated by a central conviction: that people are the ultimate unit of concern. Its frameworks (like the Human Development Index itself) are built on human-centered metrics—income, education, health, empowerment, equality—measuring progress by improvements in individual and collective well-being. The culture of this community tends to be normative and aspirational, grounded in questions of justice, rights, dignity, and opportunity. It often assumes that human ingenuity, when steered by equitable institutions, can generate the solutions to our greatest challenges. Nature is seen largely through the lens of its relationship to human flourishing: as a resource to be managed, a threat to be mitigated, or increasingly, as a partner in sustaining development.

The Earth-science community, by contrast, begins not with human aspirations but with the biophysical realities of the planet. Its models, data, and discourse are rooted in systems—climate dynamics, carbon cycles, biodiversity webs, tipping points—that operate with or without human intervention. The culture here is descriptive, empirical, and often cautionary: it emphasizes thresholds, non-linear dynamics, and feedback loops, which humans ignore at their peril. Where human development assumes agency, earth science stresses constraint; where development often speaks of rights, earth science often speaks of limits.

Both of these lenses are essential – remove either and you remove the necessary conditions for effective and informed decisionmaking at a time of genuine planetary peril. Building a fused approach will require bringing these perspectives together in a way that is both deeply informed by the best planetary science and keeps humanity at the center. 

Fortunately, a third community – the technologists – present a potential “binding agent” for collaboration between these and other, related communities of practice. New data streams (especially, but not exclusively rooted in remote-sensing) and analytical capabilities (especially but not exclusively rooted in AI and machine learning) can enable a common view across these domains, at an unprecedented level of detail in both time and space. AI can not only make the results possible, but accessible and intelligible to every stakeholder – enabling informed, real-world decision-making, and better futures, for both people and planet.

That prospect is too alluring – and fiercely urgent – to pass up.

A grand synthesis awaits.

Citation: Ellis, E.C., Malhi, Y., Ritchie, H., Montana, J., Díaz, S., Obura, D., Clayton, S., Leach, M., Pereira, L., Marris, E., Muthukrishna, M., Fu, B., Frankopan, P., Grace, M.K., Barzin, S., Watene, K., Depsky, N., Pasanen, J. & Conceição, P. 2025. An aspirational approach to planetary futures. Nature, 1–11, DOI: 10.1038/s41586-025-09080-1.

Image: Manaus, Brazil. Source: Greenpeace