For the moment, this is a purely theoretical question. If there isn’t intelligent life in our corner of the universe, then it won’t matter if we think contact is a good idea. But it’s entirely plausible that we might receive a signal someday, and it’s disheartening that so many people think we shouldn’t answer. We have every reason to think aliens would be peaceful.
Reaching the Stars Requires a Peaceful Society
When discussing what aliens would or wouldn’t be like, we have little choice but to use humanity as a model. Flawed as this approach is, it’s the only one we’ve got right now. From looking at humanity’s bloody history, many have assumed aliens would be inherently violent. This position is understandable; humans often do terrible things to each other, and we have plenty of evidence that competition is needed for advancement.
But if we assume that aliens will follow a similar path to humans, that actually makes them less likely to be violent. Violence among humans has been on a steady decline for at least a century, both in war and at the individual level. That may not feel true from watching the news, which seems more violent every day, but that’s an issue of reporting bias. We’re getting better at reporting violence, and so it seems like there’s more. At the same time, headlines about violence are more attention grabbing than headlines about people living peacefully. This is probably why Americans are afraid of terrorism but not traffic accidents.
The reasons for our decline in violence are myriad, but a major factor has been the increase in our destructive capability. As our weapons become more and more powerful, war stops being a valid option for material gain, because whatever you’re trying to get will be destroyed in the process. Humans have barely dipped a toe into space, but we’ve already reached a point where most of our powerful nations simply cannot risk going to war with each other.*
Aliens capable of reaching us would be far more powerful. They might not all be fun-loving party animals, but they would never have survived to leave their solar system if they didn’t know how to solve problems without violence. It’ll be interesting to see if we humans are capable of making that leap.
All Resources on Earth Exist Elsewhere
Another common fear is that aliens would want to crush us, not because sapient creatures are inherently warlike, but because the aliens will want our stuff. This fear also seems reasonable at first glance. Most conflicts in human history have been about resources, with moral justifications added afterwards. Aliens could easily do the same thing.
Or they would, if there was anything remotely special about Earth. This might be a blow to our human egos, but nearly anything found on our planet can be found elsewhere. Iron, water, diamonds, the list goes on. Extra terrestrial bodies are teaming with resources, many of them much easier to extract than what we have here. Our synthetic materials are even less likely to interest spacefaring aliens, for the same reason modern humans aren’t in a hurry to replace their smart phones with telegraph stations.
Even if a hypothetical race of aliens were so into mega-projects that they managed to use up the resources in their home system, there are countless star systems in our galaxy alone that don’t have a human infestation. Unless the aliens are coming from Alpha Centauri, it would be far easier to visit an uninhabited system than to come here.
Think about it: if you were presented with two soda cans, one of them covered in ants, you’d take the one without ants right? You could brush the ants off, but why bother when there’s an ant-free can right in front of you?
Crossing Space Means You Can Live in Space
While none of the Earth’s resources are unique in the cosmos, or even rare, there is one quality that makes our planet special: it supports life. It’s the only planet we know of that does. So maybe aliens would want to conquer our planet so they can have more living space for their growing population? That’s certainly the plot of more than a few scifi stories.
This concern requires that any aliens we meet can actually live on Earth, but that’s certainly plausible. For all we know, only planets with conditions similar to ours can support life. Even if the aliens can’t live here, Earth might be more like their homeworld than lifeless bodies like Venus or Mars,* and so it would be easier to terraform.
That sounds pretty grim, until we consider that before any aliens try to move in next door, they have to get here. If they can travel quickly between the stars, that means they have faster than light (FTL) technology. Modern physicists are divided about whether FTL is possible at all, but if it is, it will require energy expenditures on a level that is difficult for humans to conceptualize. Any civilization advanced enough to produce those levels of energy could just live in space.
Space habitats aren’t that hard to build. We can make them right now, it’s just expensive to send so much mass into orbit. If we could harness the energy needed to travel faster than light, we’d be building Dyson Spheres in a second. FTL capable aliens would have so much orbital real estate, the idea of flying all the way to Earth would be laughable.
Alternatively, aliens might take the slow way, crossing the interstellar void in huge generation ships. That’s an unwieldy way to launch an invasion, but it’s possible. But if they can survive for centuries in space, what reason do they even have to land on Earth? They’ve clearly mastered the art of living in the vacuum, even without the god-like technology of FTL.
We’d Be Terrible Slaves
There’s one thing we know for sure that only Earth has: humans.* Perhaps inspired by the human predilection for enslaving each other, some people think aliens would see humans themselves as a resource. Isn’t that a good reason to be scared of aliens? No one wants to get sent to the spice mines of Kessel after all.*
I’m afraid that once again, I must chip away at our sense of specialness. You see, humans just aren’t that good at working, at least not compared to robots. We’re close to automating all human labor ourselves, and that’s with puny homo-sapien tech. Compared to sleek, sexy robots, we humans are weak, fragile little monkeys that require constant food and access to toilets just to stay alive. Plus, any alien who kept a stable of humans would have to deal with constant escape attempts. Not worth the effort.
Then we get into the more exotic uses for humans. Maybe the aliens are mind-worms who need a host body to live. Or maybe they’ve just developed a taste for our succulent livers.* Either option is possible, anything’s possible with aliens, but why bother coming all the way to Earth when hungry aliens could grow their own humans at home?
In recent years, we’ve taken huge steps in the development of artificial wombs. It’s likely that some time soon, we’ll be able to create humans in a laboratory, no pregnancy required. Spacefaring aliens are almost certain to have far superior biotech, and any human-related needs could easily be satiated at home. Certainly it would be easier than crossing the vast distances to Earth.
Aliens Would Know We’re No Threat
A final reason people often give to support fear of aliens is the idea that they would want to preemptively destroy us. Better to take us out now while we’re helpless than risk humans growing in power to rival them. That certainly sounds like a reason to be afraid. If aliens decided to launch a preemptive strike, there’s little we could do.
Except everything I’ve been saying about aliens applies to humans too. By the time we’re able to travel the stars, we’ll no longer have any need for conquest. Advanced aliens would figure that out. They’d have no reason to launch a first strike. They’d know that in time, humans will either self-destruct or figure out our problems and become less terrible.
Assuming aliens would launch a first strike is a paradox. It requires that aliens be intelligent enough to build interstellar weapons, but not intelligent enough to realize humans are no threat to them. We should give ET a little more credit.
I can’t say with absolute certainty that aliens wouldn’t be hostile. No one can say anything about aliens with absolute certainty. The universe is a strange and wondrous place, and clever scifi writers are very good at finding unlikely edge cases to make their evil aliens seem realistic. But by the same token, I can’t be absolutely certain that the grocery store clerk won’t stab me next time I buy food. I go anyway, because the benefits far outweigh the risks. The same is true for aliens. Just finding out that we aren’t alone would completely change how we view the universe. And imagine if they decided to tell us stuff. Technology that seems trivial to advanced aliens could completely revolutionize life on Earth. We need to get over our fears now, so that we don’t miss the opportunity, if it ever comes.
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