If we ever make contact with an alien civilization, how will we understand what they’re saying? That’s the question that preoccupies John Elliott of Leeds Metropolitan University, one of a dozen scientists collaborating in the newly formed UK SETI Research Network. Elliott would begin by trying to verify that “they” are in fact using language—a tricky problem in itself. Thinking about such matters has led him to consider other questions, including how humans might communicate with dolphins, and the language abilities of robots. He spoke with Senior Editor Tony Reichhardt in August.
Air & Space: How did you get into this area?
Elliott: I started in computational linguistics and artificial intelligence. One day I was thinking What’s the worst case scenario to understand what language is? What if you got a message from outer space? How the hell would you tell it’s language? It was more of an academic thought experiment, to see if language structure could be identified as distinguishable from any other type of phenomenon.
What are some of the rules and patterns of a language?
One of the slides I show in my talks is loaded with zeros and ones—a binary bit stream. And the audience just goes, “uhhhhh.....” They have no idea how to interpret it. But by using algorithms, some of which are adapted from information theory, you can tell if you’ve got a language. Signals that are either random or very predictable like a pulsar would not be interesting. But if the pattern has a certain level of complexity and internal structure, where it’s broken into chunks, we’re into the communication/ intelligence ball game.
Take even very low forms of communication in the animal kingdom, like ants using chemicals to communicate, or bees doing their dance. No matter what the cognitive level, it has a particular signature. The patterns have a relationship to each other. This is something common to any information exchange. So if we were hearing something from outside our own planet, that sort of signature would be an immediate flag to say there’s an intelligence behind it.
Originally, SETI was not focused on looking for “intelligence” in a signal. It was just looking for technology—a beacon from a distant world. But if you’ve picked up a signal, the first thing anybody is going to say is “What the hell is it saying?” There’s going to be an incredible curiosity to know what it means.
The only examples we’ve got for sure are from our own planet. So I looked at over 60 languages to cover all the different ways we communicate as human beings. There are different language morphologies. Finnish and Turkish are agglutinating languages, gluing all the words together. The Aboriginal language is an extreme example. English is very much an isolating language. Each word is an isolated semantic unit. But underneath this veneer—the different sounds we make, or the different ways of ordering the parts of speech—a common signature keeps coming out.
It goes across different animal species as well. Dolphins are an immediate example, because they are next down on the intelligence scale. They’ve got a complex social structure, so there’s a similar social interaction going on. They have about 140 distinguishable types of sounds they make, and the way they use them to exchange information—the relationship of the patterns—has the same signature as ours.
And how close are we to decrypting dolphin language?