There are so many examples of human misuse of the Earth that even phrasing this question chills me. If there is life on Mars, I believe we should do … - Carl Sagan

Planetary exploration satisfies our inclination for great enterprises and wanderings and quests that has been with us since our days as hunters and gatherers on the East African savannahs a million years ago. By chance — it is possible, I say, to imagine many skeins of historical causality in which this would not have transpired — in our age we are able to begin again.

Exploring other worlds employs precisely the same qualities of daring, planning, cooperative enterprise, and valor that mark the finest in military tradition. Never mind the night launch of an Apollo spacecraft bound for another world. That makes the conclusion foregone. Witness mere F-14s taking off from adjacent flight decks, gracefully canting left and right, afterburners flaming, and there’s something that sweeps you away — or at least it does me. And no amount of knowledge of the potential abuses of carrier task forces can affect the depth of that feeling. It simply speaks to another part of me. It doesn’t want recriminations or politics. It just wants to fly.

Cosmos is for many that first encounter with the universe that you thought was foreclosed to you because you couldn’t do the math, or you live in a place where there are no scientists to invite you in. Carl wanted everyone to come on this voyage; to experience the power of the scientific perspective and the wonders it reveals. His secret was to recapture the person he was before he understood the concept and then retrace his own thought steps toward comprehension. It worked. He inspired legions to study, teach, and do science.

All inquiries carry with them some element of risk. There is no guarantee that the universe will conform to our predispositions. But I do not see how we can deal with the universe—both the outside and the inside universe—without studying it. The best way to avoid abuses is for the populace in general to be scientifically literate, to understand the implications of such investigations. In exchange for freedom of inquiry, scientists are obliged to explain their work. If science is considered a closed priesthood, too difficult and arcane for the average person to understand, the dangers of abuse are greater. But if science is a topic of general interest and concern—if both its delights and its social consequences are discussed regularly and competently in the schools, the press, and at the dinner table—we have greatly improved our prospects for learning how the world really is and for improving both it and us.