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

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 got everyone's attention, but we didn't solve any environmental problems.

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.

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.

There was almost a universal acceptance of unhealthy conditions. Sulfur dioxide in smokestack emissions were the price, or smell, of prosperity.

When we held the first Earth Day, everyone said it was a success because of the huge turnout. It was probably the largest planned event across the country.