If we lived on a planet where nothing ever changed there wouldn't be much to do. There'd be nothing to figure out. There'd be no impetus for science.… - Carl Sagan

I can talk about my father in ordinary conversation without feeling more than the slightest pang of loss. But if I permit myself to remember him closely — his sense of humor, say, or his passionate egalitarianism — the facade crumbles and I want to weep because he is gone. There is no question that language can almost free us of feeling. Perhaps that is one of its functions — to let us consider the world without in the process becoming entirely overwhelmed by feeling. If so, then the invention of language is simultaneously a blessing and a curse.

"Consider again that dot [Earth]. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there - on a mote of dust suspended in a sunbeam."

Our purportedly advanced civilization may be changing the delicate ecological balance that has tortuously evolved over the 4-billion-year period of life on Earth.