So say some of our leading scientists. Of course, not all experts agree. Carl Sagan, the inspiration behind the films ET and Contact, thought that we should spend big bucks combing the cosmos for much more intelligent life somewhere else. He even thought that such life, being benign and otherwise more "evolved" than we are, could provide us with what we need to know to free ourselves from our self-destructive tendencies.
If Stephen Hawking, for one, is right, we should do everything we can not to make our presence known. And the films Independence Day and Men in Black provide better insight into what we'll happen to us when we're found out. The aliens in Independence Day travel through the cosmos trashing one planet after another, with no regard at all for the life that might be found here or there. They're like modern imperialists and modern technologists; even Hawking, after all, says we should be thinking up some way of diversifying ourselves to other planets before it's too late. (Apparently, in Hawking's view, abandoning this planet is both good and bad for our species' survival.)
The more intelligent and techno-skilled members of our species have gotten, after all, the more they've been about the business of making their planetary environment unfit for life. And the more they can imagine that they don't need earth to survive and flourish. Why shouldn't more techno-advanced life be like us, but much more so?
One failing among many of Independence Day is we don't get any sense of who the extraterrestrial mass-muderous predators really are. But in Men in Black, we learn that self-conscious mortals throughout the cosmos are pretty much as screwed up as we are, and intelligent life doesn't get any less screwed up by getting smarter and more scientifically advanced. That makes sense: People these days aren't less neurotic or disoriented or potentially violent than people have always been. The 20th century gave us more murders than any other.
The fantasy of Sagan and Contact is that human beings have been moving from body to mind--evolving away from the basically primate (or even reptilian) causes of our territoriality, violence, and cruelty. So the more scientifically advanced people are, the more they're all about peaceful coexistence and love and all that stuff John Lennon imagined. And the transhumanists add that soon enough we'll all be smart enough to stop dying, and so all the misery of our mortality--such was jealousy and war--will wither away.
The opinion of the great author Walker Percy is that any self-conscious mortal would experience himself as alienated--as "lost in the cosmos"--without help he can't provide for himself or herself. And it's silly to believe that we earthlings could be redeemed by aliens from some other planet or place in the comos. Any being smart enough to find us would be in some sense or another a "displaced person" (like us) in a way that makes himself a potential danger to himself and others.
We already know what aliens are like by looking at ourselves. None of the ETs that have been imagined by the most talented sci fi authors is quite as strange and wonderful as the human alien we all know and love.