I think [contacting an alien civilization] would be a disaster. The extraterrestrials would probably be far in advance of us. The history of advanced races meeting more primitive people on this planet is not very happy, and they were the same species. I think we should keep our heads low.
Stephen HawkingTime travel used to be thought of as just science fiction, but Einstein's general theory of relativity allows for the possibility that we could warp space-time so much that you could go off in a rocket and return before you set out.
Stephen HawkingSo remember to look up at the stars and not down at your feet. Try to make sense of what you see and hold on to that childlike wonder about what makes the universe exist.
Stephen Hawking