Be brave, be curious, be determined, overcome the odds. It can be done. - Stephen Hawking

There's a sick joke that the reason we have not been contacted by an alien civilization is that civilizations tend to destroy themselves when they reach our stage. But I have sufficient faith in the good sense of public to believe that we might prove this wrong.

What you have told us is rubbish. The world is really a flat plate supported on the back of a giant tortoise.

If aliens visit us, the outcome would be much as when Columbus landed in America, which didn't turn out well for the Native Americans. … We only have to look at ourselves to see how intelligent life might develop into something we wouldn't want to meet.