NOTE: Revtyson edited this video from Stephen Hawking: Asking Big Questions About the Universe at TEDtalks. In keeping with the theme of TED, Prof. Hawking asks questions like: How did the universe begin? How did life begin? Are we alone? He discusses how we might go about answering them.
"We need the stars... We need purpose! We need the image; the Destiny [to take root among the stars] gives us of ourselves as a purposeful, growing species. We need to become the adult species that the Destiny can help us become! If we're to be anything other than smooth dinosaurs who evolve, specialize and die, we need the stars.... When we have no difficult, long-term purpose to strive toward, we fight each other. We destroy ourselves. We have these chaotic, apocalyptic periods of murderous craziness" (Octavia Butler, Parable of the Talents, 1998).
"I don't think the human race will survive the next thousand years, unless we spread into space. There are too many accidents that can befall life on a single planet. But I'm an optimist. We will reach out to the stars" (Stephen Hawking, interview with the Daily Telegraph, 2001).
"The dinosaurs became extinct because they didn't have a space program. And if we become extinct because we don't have a space program, it'll serve us right!" (Larry Niven, quoted by Arthur Clarke in interview at Space.com, 2001).
"In time, [a Martian] colony would grow to the point of being self-sustaining. When this stage was reached, humanity would have a precious insurance policy against catastrophe at home. During the next millennium there is a significant chance that civilization on Earth will be destroyed by an asteroid, a killer plague, or a global war. A Martian colony could keep the flame of civilization and culture alive until Earth could be reverse-colonized from Mars" (Paul Davies, The New York Times, 2004).
"We must turn our guns away from each other and outwards, to defend the Earth, creating a global and in space network of sensors and telescopes to find asteroids [and aliens out there that aliens down here do not like or want intervening in space affairs to save humanity] that could destroy our planet and create the systems to stop them. It makes no sense to dream great dreams while waiting to be hit by a train" (Buzz Aldrin and Rick Tumlinson, Ad Astra Online, 2006).
