One prominent public figure was able to match Reagan’s hopefulness and ability to inspire. She was a humble writer and farmer, but first and foremost, she was a scientist who rooted her analyses in the laws of physics and ecology (she certainly never tried to gain support by resorting to fantasy-land notions such as infinite growth on a finite planet).

Last night, with the lights out during Earth Hour, I had an epiphany. It hit me: “Wow, it’s pretty dark.”

So I took advantage of that darkness to step outside of the rational, logical thought processes I discovered have been limiting me. I realized the only thing that limits humankind is limited thinking.

For 6 years I researched and produced a film questioning our worship of growth everlasting. GrowthBusters was released in November and is today enjoying film festival and other screenings around the world. So you can imagine the shock of realizing I was completely wrong when I bought – hook, line and sinker – the silly notions advanced by such crackpot scientists as Paul Ehrlich (The Population Bomb), misguided sociologists as William Catton (Overshoot), rogue economists like Herman Daly (Ecological Economics), and the group of MIT scientists who (imagine the folly) used computer models to reach their conclusions in the Club of Rome’s Limits to Growth study. . . .

I encourage you to join millions of people around the world tonight in observing Earth Hour. From 8:30 to 9:30 p.m. turn off all your lights and unnecessary electrical devices, in a gesture acknowledging you understand and will continue to do something about the urgent need to, individually and collectively, reduce our use of fossil fuels.

Ostensibly this is necessary to reduce greenhouse gas emissions and the climate disruption they cause. Even if this weren’t the case, I would suggest it’s important we acknowledge there is a finite supply of these fuels on the planet, and we have no right to burn through most of it in 300 years, leaving none for the use of future generations. That kind of thinking is relatively new to us, but it’s the type of thinking we must do now that we’ve filled the planet with 7 billion of us. This intergenerational golden rule is one of the bases of my quest for our civilization to achieve sustainability. . . .

Tomorrow at 8:30 pm people around the world will be turning off their lights for one hour in a symbolic gesture. What does that symbolize? On the plus side, it’s a symbol of widespread awareness of the impact of humankind’s activity on the climate. It also serves as a reminder  each of us has the power to make a difference, and when large numbers of us do something, it adds up. For those reasons I’ll be participating in and supporting Earth Hour.

The truth-teller and cultural critic in me, however, also feels compelled to comment on how we can and should improve on Earth Hour. Obviously, we need to extend our awareness and our actions to the other 8,759 hours of the year. If your family observes Earth Hour Saturday night, please gather in the dark and make plans for how you will shrink your footprint throughout the year. If all you do is douse the lights an hour each year, you are wasting your time. . . .

Today’s guest post in our series honoring the 40^th anniversary of the landmark Limits to Growth study is by William Rees. Rees, along with Mathis Wackernagel, originated ecological footprint analysis. My interview with Dr. Rees for GrowthBusters was one of the last conducted before completion of the film. I left that interview thinking I could have saved myself a lot of time and trouble – rather than devoting six years to funding and producing the film, I could have simply recorded this interview and released it. In 40 minutes Bill Rees covered, knowledgeably and eloquently, nearly every topic in the film!

This is part of a paper William Rees presented at the Institute for New Economic Thinking Annual Conference in Bretton Woods one year ago. INET is doing some great work exploring what a sustainable economy looks like and how to get there. The institute’s next annual conference is a few weeks away. . . .