Photo: James Duncan Davidson

Paul Gilding starts his TEDTalk with four words that say almost everything: “The Earth is full.” It’s a terrifying concept. Have we really strained, mined and otherwise depleted the planet’s resources to the point where social collapse is inevitable? Gilding believes we have, and he launches into a defense of that notion.

He is not a hater of technology, or someone who doesn’t believe in the power of innovation. Indeed he says we are a brilliant and creative species, but so big we’ve outgrown our host. “This is not a philosophical analysis. It’s just science … We’re living beyond our means.”

The science in question is partly the numbers of years until we’re out of oil, the number of people crop yields can feed … But it’s also the unrelenting mathematics of constant growth: “We are stealing from our future.” The planet is already 50% above capacity. Our economy simply cannot sustain growth forever, and when things aren’t sustainable, they stop. And in this case, “Stop” means that civilization will collapse.

Of course, people believe that markets will overcome these obstacles, that the ingenuity and resourcefulness of scientists, technologists and entrepreneurs will find a way circumvent these problems. Gilding takes a moment to acknowledge this position, saying: “We regularly solve complex problems with amazing creativity,” but he also claims that the emperor has no clothes. We could, he says, get capacity down from 150% to 100%. But the real problem is that we’re just warming up the economy. Yet the world is collectively planning on it getting twice as big in just 40 years.

People say we need this, that growth is essential to the survival of our civilization. It’s so central that the idea itself is never questioned. Gilding is fascinated by argument that “We can bend the rules of physics to suit our needs.” In the face of the possibility that unrestrained growth will strain resources to exhaustion, people claim that without growth the world is in trouble, therefore everything will be fine.

But the truth is, “The planet doesn’t care what we need. Mother nature doesn’t negotiate.” These are not esoteric limits, they’re about food and water and basic needs. The idea that we can transition smoothly, that growth and economics as we know them will innovate the problems away, that we can gently move to a system at 100% of the Earth’s capacity is, says Gilding, a delusion. The idea that we’ll heed the warnings would make sense, but we’ve had 50 years of warnings, and what has happened? Last year there were more carbon emissions than ever in history. We know that the eventual cost will be cheaper the earlier we act, and yet we’ve never acted, “We’re not even slowing down.”

He points to all the failures around us — of government, of business, of energy supply. We see each of those as individual problems to be solved, but they’re connection: they’re symptoms of the painful process of the entire system breaking down.

Now is the surprise: Gilding is saying this not in despair, but in a form of hope — one filled with sadness and resignation of what’s come before and the collapse that seems inevitable, but also with a resolve to see what happens next, and confront it with every bit of ingenuity and determination that we, as a species, have.

He could give us evidence, but it’s all around us. What he wants to talk to us about is fear. How will we react?

Gilding asks us: “Imagine China, India and Pakistan going to war… Imagine the Middle East without oil income and with failing states. Imagine our just-in-time food system failing. Imagine 30% unemployment and a real credit default. Now imagine what that means for you, personally. Imagine how you’ll feel when a heavily armed civilian population gets angrier and angrier that this was allowed to happen” And then imagine, he asks, what you’ll tell your children when they find out we knew all these things, and didn’t act.

And the lights go out.

Gilding asks what we feel. Denial? Anger?

What we feel, mostly, is fear.

As the lights come back on, Gilding reminds us that fear is the natural human response to crisis, and one that evolved for a good reason. But fear can be paralyzing or motivating. If we can process it now, if we can think through the fear in advance, now, “While the light is still on,” maybe then we’ll be able to respond appropriately when the time comes. “Yes,” he says, “things will get ugly, soon, in our lifetime. But we are more than capable of getting through everything that’s coming.”

And the real ray of hope here: There is a lot that is right in the thinking of those who have faith in our powers of innovation. But the thing that they’re missing is that we don’t get going, we don’t really start creating and pushing ourselves to the limit, until there’s a crisis. Witness the American response after Pearl Harbor, or what any of us does in the face of a diagnosis of life-threatening illness. Says Gilding, “We are smart, but we do like a great crisis, and the good news is that this one is a monster. Sure, if we get it wrong we could face the end of civilization. But if we get it right, it could be the beginning of civilization.”

Gilding has worked with economists and other scientists. To his surprise, the cost of eliminating the excess carbon emissions is pretty cheap, “at least compared to the cost of a collapsing civilization.” But: “We need to act like we only have one planet.” (A murmur of assent ripples through the audience.)

This future that Gilding sees is a dark one, where we are fighting a war, not between civilizations, but for civilization itself. But it’s a time when we will be able to solve problems, to innovate and recreate like never before. And maybe we’ll come out of it with a stable economy, with a mature civilization, better than the adolescent one we now live in.

Gilding closes by asking us, “What do we want to be when we grow up?” And by making the bold claim that, “We can choose life over fear,” but it will take everyone of us, doing everything we can. Then, “this could be our finest hour.”