These are not exhortations from overwrought extremists, but carefully phrased warnings from some of the world's finest scientists.

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.

he economy favors throughput over quality and craftsmanship, and economists are terrified because the American savings rate has crept upward from about zero to almost five percent. But the mortgage crisis and the burgeoning credit card crisis are causing Americans to become wary of irresponsible debt.

The more subtle thing is more speculative. The world is well past its long-term carrying capacity for human beings living a European, much less an American, lifestyle predicated on planned obsolescence. International economic growth is largely a matter of accelerated movement of materials from mines and forests to the dump. Instead of saving and buying decent furniture we can pass on to our children, we charge our credit cards for shaped heaps of sawdust and glue that fall apart in less than three or four years.

Make Earth Day Every Day.” While we might not always live up to this ideal, I try to keep this quote from Denis Hayes, founder of the Earth Day Network and president of Seattle’s Bullitt Foundation, in mind when I need a little extra motivation to be a better environmentalist: “Listen up, you couch potatoes: each recycled beer can saves enough electricity to run a television for three hours.

Listen up, you couch potatoes: each recycled beer can saves enough electricity to run a television for three hours.

Earth Day gathered up those strands, and dozens more, and knitted them together in the public consciousness as "environmental" issues. The nation was pretty startled when 20 million people hit the streets. Congress, which had adjourned for the day to go back to its districts, was blown away.