Roberts recently co-authored a book, Xenolinguistics – alongside Kershenbaum, Avram Noam Chomsky and other leading biologists, anthropologists and linguists – to explore what non-human, non-Earthbound language might look like.
A theoretical linguist, Chomsky defined language as a system of communication that is infinitely adaptable, designed to serve human interests and to solve human problems – one that’s flexible enough to communicate a very large number of concepts.
“It may well be that there’s some kind of bacterial life on Mars or on the moons of Jupiter – but these would be very simple organisms,” says Roberts. “What I’m interested in is the nature of intelligent organisms. So, you have to decide, what’s the criterion for intelligence?”
The answer to that, says Roberts, is technology – a technological civilisation, comparable to ours, with the ability to get off their planet.
“Wouldn’t they be sitting there, on their planet, wondering who else is out there? Wondering whether we exist?” he says. “Let’s say a species is intelligent enough to want to build a spaceship, or a radio telescope — something complicated. You’d need to know a lot about physics and mathematics. You’d have to have the ability to develop scientific theories and to collaborate. You would have to be able to communicate a very large number of ideas to a lot of other individuals. The fact is, [other] animals have not developed technology.”
Without language, says Roberts, a technological civilisation would be inconceivable.
How alien could alien language be?
In 2022, Roberts helped to establish The Cambridge Institute of Exo-Language (CIEL), with the goal of considering how we might communicate with intelligent exo-beings, and how different alien language and intelligence could be from our own.
“My personal opinion is that, at its core, the language would have to be quite similar to ours in the sense that its formal mathematical nature would be similar to human language,” says Roberts. “But at the same time they wouldn’t necessarily have anything like speech.”