I have been writing about sustainability and sustainable development for over thirty years. Much of what I have written is outdated — based on old facts, old reflections, and old situations that have changed dramatically. Recently I found myself wondering: what, in all of that writing, might possibly stand the test of time?

So on a rainy Saturday in March, I went through some of my old books and other publications — and I was pleasantly surprised. I found quite a lot of material in those books that was still true, and still useful. I ran across a number of quotes that I still stand behind. So I paired some of these quotes up with photographs, to make them shareable on social media and the web.

Here’s the first one: “Our generation is charged with an unprecedented responsibility: to lay secure foundations for a global civilization that can last for thousands of years.”

The source of that quote is the “manifesto” I starting writing near the turn of the millennium and completed on 31 December 1999. It was first published as a standalone pamphlet by Chelsea Green (one of my publishers), then reprinted several times in magazines and books.

The exercise of writing a manifesto, which I called “Sustainability is Dead — Long Live Sustainability,” was prompted by the worries expressed by a lot of my colleagues at the time: that the concept of sustainability was getting watered down and threated to become devoid of meaning. The manifesto was my attempt to clarify sustainability to myself, since I was dedicating my working life to its advancement. Writing the manifesto was an enormously satisfying exercise. It helped me formulate a number of ideas about the universality of the sustainability vision, and the need to ground it in both absolute and realistic terms, based in our understanding of science and technology, as well as global fairness and intergenerational ethics.

Those ideas are still part of my work to this day, and they inform everything else I have written about sustainability and sustainable development since that time.

I still stand behind these words because I think they are true, and because I believe that we need to take this thought — which I am happy to admit is far from original — much more seriously.

Here are just a few of the things we humans are doing that will have impacts over thousands of years: changing the climate, depleting key resources, allowing species and ecosystems to disappear, creating wastes that won’t go away, leaving behind dangerous technological artefacts that must be kept secure for millennia.

And of course, we are setting cultural patterns in place that will probably have thousand-year echoes. Consider the fact that we still follow patterns of ancient Roman law across much of the world. Many of us work in merit-based bureaucracies first pioneered by the ancient Chinese. Here’s a provocative question: what, from today’s global culture, is also likely to survive the test of time?

Obviously, every era of human endeavor creates things that persist and affect the rest of history. There is, however, a big difference today: we are changing the whole planet, fast, and doing it in a way that we know will have very long-lasting impact. And right now, the balance of that impact is decidedly negative.

Our generation — more accurately, the several generations that are alive right now, as well as several more still to come — has to get this right. We have to put human development on a secure, sustainable course. If we do not succeed, human civilization will not succeed, and the evolution of life on planet Earth will have to recover from a period of rapid and perilous diminishment.

Not an easy reflection to keep in mind. That’s why I thought it was worth making into a small digital poster.

Which you are welcome to share.