Chris Anderson: Professor, if you had to guess either way, do you now believe that it is more likely than not that we are alone in the Milky Way, as a civilization of our level of intelligence or higher?
[This answer took seven minutes, and really gave me an insight into the incredible act of generosity this whole talk was for TED.]
Stephen Hawking: I think it’s quite likely that we are the only civilization within several hundred light years; otherwise we would have heard radio waves. The alternative is that civilizations don’t last very long, but destroy themselves.
Chris Anderson: Professor Hawking, thank you for that answer. We will take it as a salutary warning, I think, for the rest of our conference this week. Professor, we really thank you for the extraordinary effort you made to share your questions with us today. Thank you very much indeed.