Why the Aliens Don't Care (Or Why They Might)

For all that science-fiction does, whether it's great action, cool concepts, sleek environments, or probing social commentary, sometimes it can be rather lacking. Even when I first saw Independence Day, amidst the then-cool lines ("Is this glass bulletproof?") and the poignant image of Jeff Goldblum and Will Smith sharing a fag, there was the unsettling thought that the entire premise to the story was improbable. In one of the explanatory expositions in the movie, someone explains that the aliens go from planet to planet, destroying all life on the planet before harvesting its natural resources. Why? What does it need from Earth that it cannot get elsewhere? I wasn't sure, and I'm still not.

For any element or material that I can think of, they can be found on countless other worlds or asteroids that do not have life. For carbon-based compounds that result from life processes, such as crude oil and coal, they wouldn't be needed for energy, because the energy needed to cross the stars would be too high to rely on fossil fuels. It would be unlikely they would be needed to synthesize plastics or other materials, as a civilization with enough energy to cross the stars would likely have enough energy to synthesize materials akin to, if not better than, plastic. Aliens also would not likely seize us to be slaves, because if they can travel between stars, they are probably advanced enough that everything is automated. So, sorry ID4, and countless other movies (like Signs), I cannot take your basic premise.

There are several alien behaviors that seem likely, and several more that seem less likely but I'm willing to accept with reservations. Of course an alien civilization need not think in the same way, but I find I am making fewer assumptions than the more literally human-centered counterparts in Hollywood, conspiracy theories, and elsewhere.

Space is vast. Its vastness is inconceivable except in numbers, and even then is rather daunting. For the comfortable little space that the planets of our solar system rest in, and the larger Oort cloud where matter whirls about in long orbits, there is far more that is between us and any other star. There are still things out there, like bits of matter, stray extrasolar asteroids, and a lot of radiation. Then, that being set aside, there are many stars, and we are discovering that there are many planets. For a galaxy about 100,000 light years wide and 1,000 light years thick (our little dinner plate), there are over 200 billion stars. There are perhaps 100 billion galaxies. These are all interspersed in several tens of billion light years. Unless the space out there is teeming with life that we somehow have been unable to see, there is lots of room for everyone at present, and there needn't be concern for our solar system, let alone our planet, because someone needs something from the occasional planet that has life.

If they did come around anyway though, there could be a few reasons for it. The Star Trek excuse, as I call it, is to explore and observe. Life might well be curious about other life for any number of reasons, both scientific and ethical. They might do so from afar, monitoring our broadcasts and bugging our houses; they might do so close up, occasionally seizing a few people at a time; they might even do so by subtly changing the values of our civilization so that, while our lives would not be negatively impaired, they might observe what they want. I don't think the methods, or even their methodology, could be presumed, but I would like to think that anyone capable of traveling between stars would know the value of conserving life, and its similarities of conserving energy. I don't think this one is worth worrying about, any more than we worry about God or Satan interfering in our lives. They might and they might not (though I think not), but even if they do, we can't live life basing our decisions on apparitions that have nothing to do with what we immediately interact with.

Other reasons we can think of, and are perfectly human, and thus we cannot judge their likelihood on any other scale than practicality. Perhaps they just like killing other things. Maybe they like destroying other planets. Perhaps they just don't care to take the little bit of extra effort to manufacture that one amino acid that we happen to have. Perhaps they think in terms of conquering and making vassals of other sentients. Perhaps they want to spread their code of conduct to us, trading in exchange their technologies in order to create harmony in the stars. My problem is not with the premise, but with the practical question: why care about us? We are humans. If life is out there in any probability, there is lots of other life out there. If it is possible to travel between the stars, many probably do it. But they can get everything they want without wasting the energy to come here.

It makes for a decent story sometimes, and I'll suspend disbelief if the other parts of the story (action, humor, etc.) are good enough. But I wish that someone could really surprise me with a plausible premise for aliens to come here. It'd blow my mind.