An interesting article in The New Yorker on the necessity of keeping an open mind about what form an alien intelligence might take.
Yet, even as the Kepler mission gets closer to finding a mirror image of our own planet, many scientists have ceased believing that we should be looking for ourselves in space. There are other ways for a planet to support life, they argue—and there are other ways for life to be intelligent.
That’s the point of a recent paper in Acta Astronautica by the dolphin-behavior researcher Denise Herzing. She warns against the seductive tendency to turn the question of a creature’s intelligence into one about how similar that creature is to humans. Instead, she writes, we need “a non-human biased definition and measure of intelligence.” This would allow us to identify signs of intelligent life that a human-centric explorer might overlook—for instance, in creatures without limbs to manipulate their surroundings, mouths to make sounds, or even brains to process information. (After all, microbes and plants learn about and react to their environments.)
Three things always stand out to me in these kinds of discussions. The first is that the laws of physics would be the same for extraterrestrials as they are for us. That means, to some extent, there is likely to be similarities to how life here on Earth works. Environments can vary tremendously, but gravity, electromagnetism, and the other forces of nature all still apply. Convergent evolution might imply that there are only so many different body plans out there.
But the second is that nature has always surprised us with the different forms life can take, even just here on Earth. That means that while aliens will follow the same physics as us, we’d almost certainly be shocked at the other ways life can work aside from what we see here. And an alien intelligence could conceivably be so strange that we couldn’t find a way to communicate with it. Although if we can tell that they’re intelligent, it seems like some form of communication would be possible, even if its just in the form of observing the results of each other’s intelligent acts.
The third though, and I’ve written about this before, is that intelligent life almost certainly exists elsewhere in the universe, but there’s a good chance it is very far away, as in outside of this galaxy. If intelligent life is prevalent and close enough to have reached us by now, we should have been colonized long ago, or at least found some signs of past visits. (No, we don’t have those signs, despite what the Ancient Aliens people say.) Of course, we might find such a sign tomorrow in the asteroid belt, or somewhere else in the solar system.