Unknowability

What do we write about when we write about aliens? Of course, we mostly write about ourselves – even when we're writing about cat-aliens. Perhaps especially when we're writing about cat-aliens, because despite all the behavioural studies we don't, really, have any idea about what cats are thinking, what they feel, the nature of their sense of self. We can try to imagine all that, but whatever we imagine is a transposition of what we think cats might think, a reflection of a reflection of ourselves.

And when we try to write about actual aliens, who come to us not from the dark of our gardens but the dark between the stars, we're trying to fill, maybe, the gulf between our small little lives and the vast vacant uncaring unknown. When we're kids, we look up at the stars and imagine kids like us looking back, from some planet like our planet. Because recontextualising the unfamiliar in terms of the familiar is what kids do, that's their superpower. And then we grow up, and realise that outside Earth's thin envelope of air there's nothing human or familiar. When we look up at the stars, the unknown indifferently stares back.

Very near the beginning of one of the best, and probably the best known cinematic depictions of an alien encounter, 2001: A Space Odyssey, there's a scene where a family of man-apes huddled together at night under an overhang, wide-eyed, unsleeping, while the dark everywhere outside this inadequate shelter is resonant with murderous cries. And very near the end of the film, we see, in the eyes of an astronaut falling through a transdimensional wormhole opened by an enigmatic alien artifact, that same fearful gaze behind the reflections of impossible wonders flickering over a helmet visor.

We're still afraid of the dark.

Back in the 1990s, there was a belief that physicists were getting close to formulating a Theory of Everything – to reducing the complexity of the universe to an equation that could fit on a T-shirt. Such was the muscular optimism of the twentieth century. We know now that the universe is not only stranger than we once imagined: it could well be stranger than we can imagine. As Martin Rees, the Astronomer Royal, has pointed out, 'there may be some aspects of reality are intrinsically beyond us – just as quantum theory was beyond the first primates.'

This doesn't mean that the universe isn't comprehensible, only that we're only just bright enough to know that we aren't bright enough to know everything. And we also know that unless we are truly alone in the universe, or unless we've reached the outer edge of some kind of limit to intelligence that's inextricably woven into the intrinsic structure of the universe, that there are almost certainly other species out there which are considerably smarter than us. Highly-evolved species of aliens which have already figured out what mere humans simply can't.

We can only guess what they might be like. Sometimes, as in Alastair Reynolds's Revelation Space universe or John Varley's Eight Worlds future history, they treat humans and other inferior species are troublesome infestations. Sometimes, as in Olaf Stapledon's Star Maker, they keep their existence hidden from mere primitives like us because they know that even the most casual contact would blow our tiny minds. And sometimes, as in Arthur C. Clarke's Childhood's End, David Brin's Uplift series, and Ursula Le Guin's Hainish Cycle, they want to help.

The Jackaroo in Something Coming Through and Into Everywhere want to help. Kind of. Maybe. They claim, anyway, that they are here to help, and gift humanity with fifteen habitable exoplanets and the means to reach them – but they won't explain why they want to help us, or to what end, or what happened to their many previous clients. Even more than cats, they're fundamentally unknowable. Perhaps there's a universal law: any species which can sufficiently understand and manipulate the fundamental properties of the universe to traverse a significant portion of it is incomprehensible to those species, like ours, which can't.

But while we can't understand them, aliens smart enough to understand the universe would also be smart enough to have a complete theory of everything human. We can't yet understand the minds of cats, but hyperintelligent aliens could see us whole, know us in ways we can't know ourselves. They could, if they wanted to, game and manipulate us in ways we can't begin to see, for reasons we may never be able to grasp. And even if they didn't toy with us, even if they were honest and open and completely straight forward, their innate superiority would inevitably create mistrust and resentment. They would reflect not only the unknowability of the universe, but our fear that we do not, perhaps, measure up to what it expects of us.