Exploring the Future of Inorganic Intelligence in the Cosmos

It’s taken more than four billion years for intelligent life to emerge by natural selection on Earth, but there are billions more years ahead in our planet’s lifetime. Over that time, intelligence could develop in entirely new directions.

We human beings may be nearing the end of Darwinian evolution—no longer required to become the fittest to survive—but the technological evolution of artificially intelligent minds is only just beginning. Before inorganic intelligence surpasses or surpasses humans, it might only take one or two more centuries. If this had happened, our species would have been just a brief interlude in Earth’s history before the machines took over.

That raises a profound question about the wider cosmos: are aliens more likely to be flesh and blood like us, or something more artificial? And if they are more like machines, what would they be like, and how might we detect them?

Not like us

Many assume that human beings are the peak of intelligence, but it’s possible that our species may represent a stage on the path towards minds that are more artificial. This could explain why the cosmos seems so empty of life like us. If an evolutionary transition to non-organic intelligence is inevitable across the universe, our telescopes would be most unlikely to catch human-like intelligence in the sliver of time when it was still embodied in that form. It is perhaps more likely that the aliens would be the remote electronic progeny of other organic creatures that existed long ago.

The prospect of inorganic alien intelligence raises some striking possibilities. If these beings were out there, they would act and think totally differently from us. They may not want to be detected. Indeed, their intentions may be impossible to fathom. To quote Charles Darwin, “A dog might as well speculate on the mind of [Isaac] Newton.” However, we might deduce a few things.
For one, non-organic intelligence may have no use for an atmosphere or the planet on which it originated. Interstellar voyages—or even intergalactic voyages—would hold no terror for near-immortals.

Indeed, they may prefer to live in zero-gravity because there you can make very large, very lightweight objects. If you wanted to build a huge, elaborate gossamer-thin structure to harvest energy, for example, it’s easier in space than on a planet.

It’s also not obvious that they would need to live in orbit around a star. Perhaps they’d have new ways of getting energy that we just can’t envisage yet. If they have silicon-based brains, they might realize that the energy needed for processing “bits” is less at low temperatures, so they would expend less energy in colder regions away from planetary systems. They might even decide to hibernate for billions of years until the universe’s ongoing expansion further cools the cosmic microwave background, which is the leftover radiation from the Big Bang.

They may not have the same base desires as us. We have evolved, through Darwinian pressures, to be an expansionist species. Selection has favored intelligence but also aggression. But if Darwinian pressures do not apply to these artificial entities, there’s no reason why they should be aggressive. They may just want to have deep thoughts.

There may still be some out there, even though we haven’t seen any and haven’t experienced their invasion. They may simply be more contemplative. We can’t assess whether the “great silence” of the cosmos signifies their absence or simply their preference. We also can’t assume that they’d even be “civilizations.” On Earth, this term connotes a society of individuals; in contrast, ET might be a single, integrated intelligence.

Pessimistically, they could be what philosophers call “zombies.” It’s unknown whether consciousness is special to the wet, organic brains of humans, apes, and dogs. Might it be that electronic intelligences, even if their intellects seem superhuman, lack self-awareness or inner life? If so, they would be alive but unable to contemplate themselves or the beauty, wonder, and mystery of the universe. A rather bleak prospect.

Alternatively, their more advanced intelligence could well allow them to understand crucial aspects of reality that we cannot, just as a monkey can’t understand quantum theory. There could be complexities to the universe that neither our intellect nor our senses can grasp, but electronic brains may have a quite different perception.

Implications for searching

If alien intelligence is more likely to be non-organic, what would this mean for the Search for Extraterrestrial Intelligence (Seti)?
In a decade or two, there’s a realistic prospect that we’ll have the capability to detect biosignatures on other planets—atmospheric chemistry or vegetation, for example. But to detect artificial life, we would need to look for “techno signatures,” such as electromagnetic transmissions.

The focus of Seti has been on the radio part of the spectrum. But of course, in our state of ignorance about what might be out there, we should explore all wavebands: the optical and X-ray bands. Even if messages were being transmitted, we may not recognize them as artificial because we may not know how to decode them. Consider the difficulty a veteran radio engineer familiar only with the amplitude modulation of the 20th century might have decoding modern wireless communication.

Finding non-organic intelligence also means being alert to evidence of non-natural phenomena or activity, even within our own solar system. It was right that the Green Bank telescope stayed pointed at Oumuamua, the anomalous object that passed through our neighborhood recently and is believed to have originated from outside our solar system. It’s also worth keeping an eye open for especially shiny or oddly-shaped objects lurking among the asteroids. We may also need to seek evidence for non-natural construction projects, such as the “Dyson Sphere,” a giant, hypothetical energy-harvesting structure built around a star.

In sum, astronomers like me should expect surprises. We ought to be open-minded and make sure that we don’t miss anything odd.

Scientists still don’t know whether the origin of life is rare and only happened here on Earth. But if that’s not the case, and if life gets started elsewhere, then intelligence could evolve in all sorts of ways. There are planetary systems out there that are at least a billion years older than our own, so it’s possible that intelligence has already developed into something nonorganic.
Perhaps whatever is out there doesn’t evolve by Darwinian selection; it would be what I call “secular intelligent design” that’s a bit like machines designing better machines. And while it may not be broadcasting its existence to us, it could be found throughout the universe.
Written by Martin Rees