There’s a recent paper that claims we could very well be the only civilization in the universe. As Ethan Siegel has pointed out, the paper is more speculation than science, but it has generated a lot of buzz in the media, often with sad laments over our lonely fate. But how bad would it actually be? Suppose the paper is right, and Earth is the only living planet in the cosmos. A single pale blue dot in a sea of empty dark. What would that really mean?
To begin with, we wouldn’t have to worry about alien invasions. No big eyed monsters wanting to have us for supper, no alien shapeshifters trying to replace government leaders, no red scare from Mars. Human history is filled with violent attacks of one civilization against another, and so we’ve extended our history into hypothetical interstellar conflicts. But while these tales can make for exciting stories, they aren’t very realistic. The energy, heavy metals and water necessary for a civilization like ours are plentiful in the universe, so there’s no reason for aliens to target Earth. We might imagine an alien culture so xenophobic that it tries to extinguish any competition, but such a species would likely self destruct through aggressive infighting.
A more realistic existential threat could come merely from contact with another intelligent species. Imagine if we connected with a species 100,000 years more advanced than our own. One that had solved the challenges of violence and ecological collapse. One that could travel between stars as easily as we take a train. Humanity would be forever in the shadow of almost god-like creatures, and our culture would become either a reflection of or reaction to their civilization. In our own history we see languages die, and cultural traditions fade. Would human culture be consumed by this advanced society? What would we have to offer such a culture beyond quaint amusement?
But we really could be alone. Unless and until clear contact is made with another civilization, we truly _are_ alone. Looking up at the night sky we see stars we migh visit, planets we can someday call home, and a cosmos full of potential. We are not beholden to other civilizations, and so humanity can forge its own destiny. We can become the best of our hopes or the worst of our nightmares. We can continue to fight among ourselves, or we can recognize our common heritage as step out into the heavens. Alone in the universe the choice is truly and completely ours. Our triumphs, and our shame.
Regardless of whether other civilizations exist, perhaps the best choice is to strive as if we are alone. Rise to meet our own challenges, and strive to be better than our past. And if we do happen to encounter another civilization, humanity can face them not with fear, but as equals.