Scientists disagree on the timeline of collapse and whether it’s imminent. But can we afford to be wrong? And what comes after?

“It is now too late to stop a future collapse of our societies because of climate change.”

These are not the words of a tinfoil hat-donning survivalist. This is from a paper delivered by a senior sustainability academic at a leading business school to the European Commission in Brussels, earlier this year. Before that, he delivered a similar message to a UN conference: “Climate change is now a planetary emergency posing an existential threat to humanity.”

In the age of climate chaos, the collapse of civilization has moved from being a fringe, taboo issue to a more mainstream concern.

As the world reels under each new outbreak of crisis—record heatwaves across the Western hemisphere, devastating fires across the Amazon rainforest, the slow-moving Hurricane Dorian, severe ice melting at the poles—the question of how bad things might get, and how soon, has become increasingly urgent.

The fear of collapse is evident in the framing of movements such as ‘Extinction Rebellion’ and in resounding warnings that business-as-usual means heading toward an uninhabitable planet.

But a growing number of experts not only point at the looming possibility that human civilization itself is at risk; some believe that the science shows it is already too late to prevent collapse. The outcome of the debate on this is obviously critical: it throws light on whether and how societies should adjust to this uncertain landscape.

Yet this is not just a scientific debate. It also raises difficult moral questions about what kind of action is warranted to prepare for, or attempt to avoid, the worst. Scientists may disagree about the timeline of collapse, but many argue that this is entirely beside the point. While scientists and politicians quibble over timelines and half measures, or how bad it’ll all be, we are losing precious time. With the stakes being total collapse, some scientists are increasingly arguing that we should fundamentally change the structure of society just to be safe.

Read more: Vice