As a student of conservation biology, I believe that characteristics with survival value will ultimately prevail. There is no survival value in pessimism. If you think failure is inevitable, that view will probably become self-fulfilling.

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

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

The easiest way to make something cool is to get cool people to do it. Part of this might mean the president has to forget tensions with opponents, or people like Arnold Schwarzenegger who has actually been decent with oil issues. Maybe he needs to pull some of the cool people in and make them model the right behaviors.

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.

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

As a student of conservation biology, I believe that characteristics with survival value will ultimately prevail. There is no survival value in pessimism. If you think failure is inevitable, that view will probably become self-fulfilling.