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.

We've made some heroic efforts, but the Earth as a whole is in worse shape today than 30 years ago, ... There's been 30 more years of greenhouses gases, species extinctions and population growth.

With time environmental issues got much more complicated. It is pretty easy, if you know what you are doing, to stop a company from pouring poison into a lake where kids swim. It is much harder to address all the myriad greenhouse gases emitted by different sources - from petrochemical refineries to hundreds of millions of peasants cutting down trees for their incredibly inefficient cook stoves.

An acre of windy prairie could produce between $4,000 and 10,000 worth of electricity per year - which is far more than the value of the land's crop of corn or wheat.

Whether you are buying a car or casting a ballot, choosing a job or planning a family, follow your moral compass. Don't let others define you. Don't let advertisers mold you; don't let zealots ensnare you; don't let conventional wisdom trap you....you are part of a much larger whole.

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.

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.