For a week we’ve explored the 1972 Limits to Growth study and the power of exponential growth (yet to be apparent in our wheat doubling demonstration). If you’re just now joining the conversation, explore the series here. We’ll have more, but right now you may be wondering what you can do with this information. It can be a bit daunting. Breaking the chains of growth addiction – whether it’s your own addiction, your town’s, or our society’s, seems difficult, if not impossible. Yes, in my view that’s about right. On a degree of difficulty scale of 1 to 10, this is a 15. But we actually can pull it off. We just have to break it down into a short laundry list of attitudes and behaviors, and then get busy checking them off. . . .

This is day three of our exponential growth experiment/demonstration. It’s not too late to jump into this little adventure – and bring your kids, your class or your co-workers along for the fun. You can catch up quite quickly. We began with an empty beaker (you can substitute a jar, pitcher, test tube, etc.) and a large bag of wheat, barley, rice, cheerios, marbles, or…you get the picture.

On day one we simply placed one grain of wheat in our beaker. On each successive day we double the number that were in the beaker the day before. So… on day one we had one, on day two we were at two, and today we double that for four grains in the beaker: . . .

This is day two of our lab experiment demonstrating the power of exponential growth. Yesterday we placed one grain of wheat in our beaker. Here’s what that looked like:

Today we will double the number of grains in our beaker. Tomorrow we’ll double that. This represents just under 3% growth per hour. It’s not too late for you to join us in this demonstration. Get your family involved, or co-workers, or fellow students. Share your photos, videos or experiment stories with us in the comments below.

For forty years, the scientists who developed the computer models behind the Club of Rome‘s Limits to Growth study have watched as their recommendations were ignored. Visiting with Dennis Meadows a couple of year ago I believe I could sense the toll that had taken. In my own case, I’ve been busting growth addiction for only 25% of that time, and I feel pretty weary at times. . . .

There are two components to making our civilization truly sustainable. One is changing our own personal behavior – how much energy and resources we consume in our daily lives, as well as how many children we have and how soon we start our families. The other is changing the system – public policy goals and system structures. Today public policy almost universally seeks and subsidizes growth.

Getting elected leaders to eschew the outdated and destructive goal of perpetual growth is one of our biggest challenges. First, we have to get them to question unexamined assumptions about growth being the path to prosperity. Second, we have to free them from being handcuffed to growth by campaign funding from growth profiteers. . . .

40 years ago today, a group of MIT scientists made their first public report on a study that came to be known as Limits to Growth. They had used systems dynamics to build a computer model of human activity on Earth. They called the model World3. Today I want to share a clip from GrowthBusters about that landmark study:

The business-as-usual scenario played out by World3 sounded an alarm – that we need to make some changes if we want to avoid overshooting the capacity of the planet and the ugly collapse that would ensue. For the next 40 years we kept hitting the snooze button.

Now, on the occasion of the 40th anniversary of that study, it is time for a new wake-up call. From today through Earth Day, I intend to honor that study and reawaken the discussion surrounding limits to growth on a finite planet. I’m not alone in this quest. Many brilliant, articulate experts have agreed to share their thoughts with us. And the Club of Rome, which commissioned that original Limits to Growth study, will have a lot going on, too. I have some twists, turns and surprises planned along the way. So fasten your seatbelt! . . .