What Would It Take to Imagine a Truly Alien Alien?

Thomas Nagel’s essay “What Is It Like to Be a Bat?” unfortunately does not endeavor to answer its titular question. (As a friend put it, it should actually be called “We Will Never Know What It’s Like to Be a Bat, Alas.”) But Nagel is not even interested in questions of batness. His project is to interrogate “the mind–body problem,” the struggle in philosophy or psychology to reduce the mind and consciousness to objective, physical terms. But around the edges of Nagel’s project, like tasty crumbs, we can grab at some useful ideas for imagining minds even stranger than bats: the minds of intelligent aliens. 

First, Nagel gives us a helpful entry into the question of consciousness. He writes, “The fact that an organism has conscious experience at all means, basically, that there is something it is like to be that organism.” Consciousness, then, is the ability to experience existence. It does not require intelligence, thought, or self-reflection, just the awareness of being. Nagel awards consciousness to far more animals than we might think of as humanlike or intelligent—not only bats but also mice, pigeons, and whales. Nagel chooses bats because, as mammals, he believes they are safely attributed consciousness; but, in an inversion of the swimmer who finds himself beheld by a familiar consciousness in a whale’s eye, Nagel writes, “even without the benefit of philosophical reflection, anyone who has spent some time in an enclosed space with an excited bat knows what it is to encounter a fundamentally alien form of life.”

A bat’s presence is plenty alien, the frenetic flitting and chirps; what we know of their senses confirms it. “Bat sonar,” Nagel writes, “is not similar in its operation to any sense that we possess” and “there is no reason to suppose that it is subjectively like anything we can experience or imagine” (emphasis mine). It’s not just that bats perceive the world through a different sense; we cannot assume that their experience of a sonar world can be mapped at all onto our visual world. And that’s before even getting to the ways that living by sonar rather than sight would shape a consciousness beyond simple perception.

Just as bats make their way in darkness, so too do creatures in the darkest depths of the sea. On worlds with subsurface oceans, like some of our outer-solar-system moons, the whole livable environment would be completely lightless. It’s a rich and strange ecosystem for science fiction writers to imagine us into. In James L. Cambias’ A Darkling Sea, intelligence has evolved on just such a world. Deprived of sunlight, the whole ecosystem draws energy from undersea volcanic vents, so life—and society—concentrates around these structures. And here, Cambias imagines people who look something like massive crayfish. He brings us inside their experience, a world known through a rich sonar that senses space as well as language. It changes their perceptive abilities, and their sense goes beyond the receptive—they perceive the world in vague shapes through passive sonar until they send out a click that gives clarity but also reveals their query to anyone who might be around to observe. (It is a book with lots of sneaking.) A loud noise can effectively blind them, as can too many other people talking at once.

When writer Charles Foster set out to understand a set of animals—badger, otter, fox, deer, and swift—he did so by living like them, and among them, for weeks at a time. As he writes in Being a Beast, he finds himself tuning into his senses, like smell, in new ways, and discovers a powerful connection to his animal compatriots. But, Nagel might point out, Foster learns what it is like for a human to be like a badger; we still cannot know what it’s like for a badger to be a badger. “If I try to imagine this”—Nagel refers here to a bat being a bat, but it easily applies to badger (and alien)—“I am restricted to the resources of my own mind.” He argues that whatever we imagine is an alteration to human consciousness; it is impossible, he says, to imagine batness qua bat.

So then science fiction illustrates the challenge of imagining alienness qua alien. Even if aliens evolve intelligence as we do, even if they speak a language we can learn to understand, even if we can befriend them and love them, whether because of convergence or because everyone is smart enough to make it work (a bat can never help you learn its language)—even with all of that, the alien heart may still be unknowable.

But it’s not only bats and aliens—fictional or optimistically imagined—who brandish subjective experiences we cannot understand. Nagel cites his own inability to understand “the subjective character of the experience of a person deaf and blind from birth.” Across human abilities and cultures, there are myriad ways in which our sensory capabilities and even our cultures and languages render our subjective experiences of the world incomprehensible to others of our own kind. Some languages have more words for basic colors than others—some naming only dark, white, and red, while others, like Russian, divide blue into light and dark the way English differentiates red from pink. But still, research has shown that even people without different words for, say, blue and green, can differentiate between the two. Though when we each make our way through the world, who knows what different things we see.

A relatively well-known factoid is that Homer writes of the “wine-dark sea” because the Greeks had no word for blue. He looked at the ocean and saw something different than we do. But Maria Michela Sassi, professor of ancient philosophy at the University of Pisa, gives a deeper illumination to the issue.

In her essay, “The Sea Was Never Blue,” Sassi writes that, well, first of all, Homer did have words at least for aspects of blue: “kuaneos, to denote a dark shade of blue merging into black; and glaukos, to describe a sort of ‘blue-gray,’” as in gray-eyed Athena. But indeed, the sky was “big, starry, or of iron or bronze (because of its solid fixity),” and the sea was “whitish” and “blue-gray,” or “pansylike,” “winelike,” or “purple.” But neither sea nor sky was ever simply blue.

This didn’t apply only to our familiar blue expanses. Sassi gathers examples of Greek descriptions that would seem patently wrong to a modern reader. “The simple word xanthos covers the most various shades of yellow, from the shining blond hair of the gods, to amber, to the reddish blaze of fire. Chloros, since it’s related to chloe (grass), suggests the color green but can also itself convey a vivid yellow, like honey.”

We know grass and honey are not the same color—did the Greeks somehow not?

Human eyes haven’t changed in the past 2,500 years, though in 1858 the classicist and eventual British prime minister William Gladstone did propose that, as Sassi puts it, “the visual organ of the ancients was still in its infancy.” But while Gladstone’s conclusion was wrong, he was doing his best to explain the fact that ancient Greek writing reflects a particular sensitivity to light, not just hue.

Our contemporary understanding of color is primarily defined by hue—the position on the rainbow spectrum—with variations in lightness, or value. (Red and pink have the same hue, but pink has a lighter value.) There’s also saturation, the intensity of the color—vivid blue versus the less saturated gray-blue.

Sassi sees in Greek descriptions of color more emphasis placed on saliency, which is how much a color grabs your attention. Red is more salient than blue or green, and sure enough, Sassi finds that descriptions of green and blue in Greek are more focused on the qualities that grab your attention than on the rather unsalient hues. She writes, “In some contexts the Greek adjective chloros should be translated as ‘fresh’ instead of ‘green,’ or leukos as ‘shining’ rather than ‘white.’” It wasn’t that the Greeks couldn’t see blue, they just didn’t care about blueness as much as other qualities of what they were seeing.

And so, the sea to Homer was not primarily blue. Wine was not a shabby hue approximation, but a precise description of the sea’s other visual qualities: its movement, its sparkle, its reminiscence of “the shine of the liquid inside the cups used to drink out of at a symposium.” Homer and his contemporaries saw all the colors we see today, but they noticed different things about them.

These are relatively minor differences, yet they have left many people to believe that ancient Greeks either physiologically could not see blue or could not describe it. Is language reflective of a culture’s values and worldview, or does it limit the possibilities of experience? What is it like to walk through the world seeing light’s movement instead of its color? What is it like to be a bat? We can hardly imagine. What is it like to see the sea if you are Homer?

Some of these gaps may be only minor hurdles—you say potato, I say wine-dark sea—but others may prove to be barriers to communication. And they start to do weird things with the empathetic imagining of fiction. A truly alien alien, likely as their existence may be, is so incomprehensible that stories about them just become stories about human beings.

In Stanisław Lem’s 1961 novel Solaris, humans have discovered a planet they’ve named Solaris, where the surface is almost entirely covered by ocean, and they’ve built a small station on its shores for study. They call it an ocean, but we realize, over the course of the book, that it is an ocean only in being a vast body of liquid matter. It turns out to also be a body, a planet-spanning entity of some sort. But almost everything else about it is unknown. Is it conscious, is it intelligent, is it aware of its human visitors? Are the vast shapes it exudes from its own substance daydreams or reflexes or attempts at contact?

Lem walks us through these musings as his main character, a human psychologist named Kris Kelvin, flips through the books of the Solaris station’s library. (Ah, midcentury sci-fi, where we can imagine vast and incomprehensible alien life, but not the digitization of information. There is still, in this future, microfiche.) Lem conjures a century’s worth of scientific research and discourse, the theories and schools of thought competing for correctness within the discipline called Solaristics. But the narrative encounters—of a human facing the alien ocean—can only ever tell us about the humans.

In one scene near the end of the book, Kelvin makes his first visit to the shores of the ocean. He has what we learn is a common first encounter on Solaris. As the ocean’s waves lap the shore, Kelvin reaches out a space-suited hand. The wave, being far more than mindless matter, reaches up and envelops his hand, leaving a tiny pocket of air around it. Kelvin moves his hand; the wave follows. “A flower had grown out of the ocean, and its calyx was molded to my fingers. I stepped back. The stem trembled, stirred uncertainly and fell back into the wave, which gathered it and receded.” It is the simplest and gentlest gesture of contact, like E. T. reaching his lit finger toward Elliott’s, or the sea stretching to tousle Moana’s hair—but that lacuna of air between the human hand and the alien always remains. The metaphor is not hard to untangle. Contact, Lem proposes, is impossible.

But, perhaps because of that fact or as its cause, Solaris is not really a book about aliens, it’s a book about people, the human characters. Kelvin arrives on the station to find the mission leader dead by suicide, one scientist holed up reclusive in the laboratory, and the other seemingly on the edge of madness. The ocean, it turns out, has taken notice of humanity, following a bombardment of X-rays from the station: The humans wanted to force the alien to react, and it has. And Kelvin soon discovers how. He wakes to find with him in his bedroom his ex-wife, Rheya, who has been dead for a decade and is absolutely not on Solaris with him. The ocean is sending to the humans visitors, flesh-and-blood re-creations crafted from their memories. Rheya is 19 again, as Kelvin last knew her, and she knows only what he also knows. (Another … quirk, let’s say, of midcentury science fiction: The women here exist only as projections of men’s memories of them.) But the ghostly visitors are not just manifestations of memory, they’re Solaris’ doing. When I spoke to dolphin researcher Kelly Jaakkola, she said, “An interesting question to me is, If there was a blob on the wall, what would it need to do to get me to think that [it was intelligent]? I think one of those things would be a rational imitation … Not necessarily like a mirror, because a mirror is not intelligent, but in a more purposeful kind of way.” Replace a blob on the wall with a planet-spanning ocean body and you see where we are. Dolphins can imitate other dolphins or humans even without sight, listening and echolocating to determine the actions of the other swimmer in their pool. What senses might Solaris have? What might it mean with these mimicries?

We, and the visiting humans in Solaris, can ask these questions, but answers never come. So Kelvin’s delvings into the books of Solaristic history and theory sit amid scenes of emotional impact that take place between humans—or between humans and approximations thereof.

A truly alien alien like the ocean of Solaris can’t be a character in a story. I don’t know what Solaris’ ocean signified to Lem, or what he envisioned happening beneath its waves. Perhaps the alien ocean is merely meant to be a confounding presence, a wall the humans slam their heads against, the story contained in their bruises.

Excerpted from The Possibility of Life by Jaime Green, Copyright © 2023 by Jaime Green. Published by Hanover Square Press.