Stephen Hawking says the mathematical probabilities that aliens exist somewhere in the universe make it tough to deny that they do. But what's great about this article is that he believes that based on our own history we probably shouldn't be in such a hurry to reach out and communicate with them.
"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.”
Yeah, but then we also have a habit of not paying attention to history, or choosing to collectively forget it.