Our planet is indivisible. In North America we breathe oxygen generated in the Brazilian rain forest. Acid rain from polluting industries in the American Midwest destroys Canadian forests. Radioactivity from a Soviet nuclear accident compromises the economy and culture of Lapland. The burning of coal in China warms Argentina. Diseases rapidly spread to the farthest reaches of the planet and require a global medical effort to be eradicated. And, of course, nuclear war imperils everyone. Like it or not, we humans are bound up with our fellows and with the other plants and animals all over the world. Our lives are intertwined. If we are not graced with an instinctive knowledge of how to make our technologized world a safe and balanced ecosystem, we must figure out how to do it. We need more scientific research and more technological restraint. It is probably too much to hope that some Great Ecosystem Keeper in the sky will reach down and put right our environmental abuses. It is up to us. It should not be impossibly difficult. Birds - whose intelligence we tend to malign - know not to foul the nest. Shrimps with brains the size of lint know it. Algae know it. One-celled microorganisms know it. It is time for us to know it too.
Carl Sagan
1934 - 1996