Stephen Hawking says that we shouldn’t try to contact aliens, lest they come and attack us for our resources:
Hawking believes that contact with such a species could be devastating for humanity.
He suggests that aliens might simply raid Earth for its resources and then move on: "We only have to look at ourselves to see how intelligent life might develop into something we wouldn't want to meet. I imagine they might exist in massive ships, having used up all the resources from their home planet. Such advanced aliens would perhaps become nomads, looking to conquer and colonise whatever planets they can reach."
He concludes that trying to make contact with alien races is "a little too risky". He said: "If aliens ever visit us, I think the outcome would be much as when Christopher Columbus first landed in America, which didn't turn out very well for the Native Americans."
I can’t get too worried about this. It seems to me that any alien civilization with the technology to get here and attack us would also have the technology to search telescopically for planets with useful resources. We’ll probably be able to do a decent job on that ourselves within the next decade or two. To be specific, we’ll be able to do spectroscopy on the atmospheres of lots of planets, which would give us a good idea of which ones to go to and mine — if only we could get there.
For anyone who wants to find us, get to us, and exploit us, finding will be by far the easiest step, so this doesn’t strike me as a good argument for hiding.
Of course, there may be other reasons for not broadcasting our presence to aliens, the most obvious being that it’s a poor use of resources. It all comes down to a cost-benefit analysis: Hawking doesn’t want to do it because of the potential cost (alien attack); I’m more concerned about the (overwhelmingly likely) lack of benefit.
I haven’t yet read the original, but this seems like a Big Goof on Hawking’s part, comparable to James Randi going over to the dark side (since then partially retracted, but AFAIK only partially) of global-warming denialists (particularly embarrassing was the exact group he defected to). It must be obvious to anyone with even a basic understanding of the issues that we could not hide from any advanced civilisation even if we wanted to. Also, apart from SETI-style deliberate broadcasts, there are all those reruns of I Love Lucy (and, yes, Hawking guesting on Star Trek) expanding around us at the speed of light.
I have to agree with you both on this. I also disagree with Hawking that they might want to utilize Earth’s resources. Firstly, Earth is running out of oil, coal, gas etc because we are consuming it -I cannot imagine an Alien race far more intelligent than human beings believing that coming to Earth to steal our already near-depleted resources was a good idea. Even we don’t think using up these resources is a good idea. And even if by “resources” Hawking is talking about the water on earth. If there is water on earth there is water on millions of other planets and even more water on these other planets – such as the water that is believed to be on one of Jupiters moons that is thought to have far more water than on Earth. And that is in our solar system – I’m sure that there is a planet nearer to these aliens that has even more water. But who am I to argue with Stephen Hawking…