IN The Story of Change, an animated short film by Annie Leonard, a shopper is hauled before a judge for the contents of her trolley.
"Wait a minute," Ms Leonard says, in the voice-over. "My fault?"
The typical story of "going green" by shopping smarter has serious shortcomings, she argues. If we're really going to make change, it's our "citizen muscles" we need to exercise, not our '"consumer muscles".
Last month, Ms Leonard visited Australia from the US to speak at the Sustainable Living Festival in Federation Square, sponsored by the phone-recycling program MobileMuster.
In 2007, Ms Leonard - a long-time environmental advocate - made her first video, The Story of Stuff.
The 20-minute clip was an astounding success: it has now been viewed more than 15 million times.
Altogether, the eight animations in her series have been seen more than 36 million times. They cover topics from electronics, cosmetics and bottled water, to the economic crisis, cap-and-trade policy, and corporate funding in politics.
Ms Leonard says that while the details of our dilemmas are complex, the big picture is straightforward: "We're simply using too much stuff. Our use of fossil fuels has dangerously altered the entire planet's climate, threatening millions and millions of people immediately and potentially destroying the planet's ability to sustain life. That is a really big problem."
The trouble with responding only by altering our consumption - the idea that our dollar is our vote - is that corporations have much more money and influence.
That's where her latest film, The Story of Change, comes in. It explores the steps beyond greening your home, with reference to great social movements such as the campaigns for civil rights and Indian independence, and against apartheid in South Africa.
"We stress about buying the least toxic products, driving fuel-efficient cars and changing our light bulbs. While those are all good things to do, they aren't commensurate with the scale of the problem," she says. "The decisions that have the greatest impact are not those made in supermarket aisles, but those made in halls of government and boardrooms of businesses - and that's where we need to be using our citizen muscles to work for bigger, bolder change. We can't shop our way to sustainability."
Even shopping less isn't sufficient. Sharing instead of buying, growing your own food and composting at home are all "good places to start, but they are terrible places to stop".
"We need to move from making change in our kitchens to making change in our communities," she says.
But how? "Pick an issue that excites you," Ms Leonard suggests. "Better bike lanes? Ending government subsidies for the super-profitable coal industry? Figuring out how to reduce packaging? Investments in clean energy? It's always easier - and more fun - to do things with others. So once you have figured out what you want to work on, join with a friend or call an organisation working on this issue."
Ms Leonard recalls that as a university student three decades ago she thought working on environmental issues was just one option among many ways to contribute in the world. But since then, the problems have grown so dramatically that "we all have to be environmentalists wherever we find ourselves".
"'This is an all-hands-on-deck moment; we need to work together in every way we collectively can."
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