Or they will do what every single human being on the face of planet Earth has done when encountering a civilization with significantly less advanced technology for the first time: Rape, Pillage, Murder, Enslave and Steal.DasMark said:Probably this. If there's (at least) one intelligent race out there (which, with the laws of probability and just how fucking big our universe is, is likely) they're probably going to avoid us until we know better than to shoot them down or try to kill them.
Because wave your peace flag all you like, you know as well as I do that with the world being the way it is now, an alien would show up, someone would say the T-word, and then missiles would be flying and we'd all be doomed to sweat under the lash of our nine-tentacled alien overlords.
Unfortunately, since they are aliens, they're thought patterns, values and various other determinants for decision making are alien to us. As such, no human can predict what they will do. I find it highly unlikely we will be left alone until our technology rivals theirs though.
What possible basis could Sagan have to make that statement with any sort of definitiveness? There is just as much factual bearing to claim any spacefaring civilization will behave like the Orks from Warhammer 40k.Omikron009 said:Not for a long time. If there are sentient life forms capable of interstellar space travel they'd probably leave us alone until we can sort out all of our issues, and any nonsentient or non spacefaring life would have to be discovered by us, and we won't be leaving our solar system for a few hundred years. I'm pretty sure that Carl Sagan said in cosmos that if a race is able to survive long enough to develop interstellar space travel then they probably will have left war behind a long time ago, so that leaves the possibility of hostile alien invasion, thankfully, quite slim.
Humanity is almost guaranteed to be killing each other still when we reach the level of interstellar travel. If human nature hasn't changed in over 200,000 years, it's not going to change significantly in the next few centuries.
Edit:
On topic, it's impossible to tell when we will make first contact. It could be tomorrow, it could be in 40,000 years. There's no way to tell.
That said, my random guess is within 100 years of FTL travel/exploration. And it will involve one or more parties trying to murder the other.