It is already too late to avoid mass starvation.

We shouldn't fuel the future with the polluting methods of the past, ... We have the technology to power our future in ways that don't threaten our health or poison our planet. Let's choose to use it.

America has the technology and resources to meet all its energy needs while safeguarding the earth's climate. The urgent question now is, 'Do we have the will?' At least one city does, and I'm proud to live in it.

By 1975 - and continuing to today - all Americans came to believe that they had a "right" to a safe, clean, healthy environment. When I grew up, no one seriously criticized the steel mills and paper mills for the deadly stench they produced - that was the smell of prosperity. In the modern society, no one would tolerate such conditions in an American city.

When civilization stands at the edge of a cliff, a step forward doesn't make much sense.

There really wasn't an environmental movement 30 years ago. The Sierra Club national office in 1969 consisted of one full-time volunteer.

By the year 2000, such renewable energy sources could provide 40 percent of the global energy budget; by 2025, humanity could obtain 75 percent of its energy from solar resources.