About everything's interdependence...
This we know, the earth does not belong to man, man belongs to the earth. This we know. All things are connected like the blood which unites one family. All things are connected. Whatever befalls the earth, befalls the sons of the earth. Man did not weave the web of life, he is merely a strand in it.
Whatever he does to the web, he does to himself.
-Chief Sealth (Seattle)