There’s been work going on for a while, maybe since the late 1990s. But it’s sporadic, and the problem is gathering data. With human language, we’ve now got the Internet, and billions of words to analyze. I’m working with the Wild Dolphin Project in Florida when I can. They’re trying to get enough data to have comparable analysis to what we do with human beings. Up to now, we’ve seen enough [of dolphin language] to realize that the system they’re using to communicate is just like ours in the sense of internal structures.
What they’re actually saying is a mystery still. There was a recent report that confirmed something we knew ten years ago—that dolphins have their own names that they blurt out at the beginning of an exchange to say “this is me.” They have identifiable call signs as individuals.
If you listen to language, the same rhythms and structures come out. It doesn’t matter what language you’ve got. You know it’s language being spoken.
What are some of the structures?
There are two major classes of words that humans use. Function words—the ifs and buts that act as the glue. Then you have content words, the nouns and verbs that describe the world around you. If you go across languages, the relationship between the two types has a pattern. You never have more than about nine content words put together in a chunk like a phrase. Our brain has a limit in cognition. We can hold seven to nine pieces of information at a given moment.
I compared that with dolphins, and the limit was coming out about five-ninths of our own. That reflects exactly their encephalization quotient—the relation of brain size to body mass. So the language reflects brain size, and therefore cognition. I haven’t gone through the whole animal kingdom, but I’d love to. The small amount of evidence up to now suggests a relationship between the complexity of an animal’s communication system and brain power.
If we were to receive an unknown extraterrestrial communication, we’d be able to do that kind of analysis. Short, frequent “words” are usually a type of glue for a language, but larger, more complex ones are the semantic content. So looking at the ratios of those two could tell you about the cognition of the author, their level of intelligence.
Have you already got the software to do that analysis?
I’ve got a suite of small programs, though not a single application that will analyze everything at a single push of a button. Collectively I call it Natural Language Learner for SETI. If you pulled in a binary bit stream [of an extraterrestrial signal], you could immediately analyze and show the complexity and internal structure. Then you could analyze the relationships of the identified patterns, to help assign categories of linguistic behavior. In addition, I have programs that could categorize analog signals by analyzing their overall structure and rhythm.
I’ve also written papers on the decipherment strategy, post-detection. Assuming there’s no “crib” or Rosetta Stone to help us decipher [the message]. In that worst-case scenario, everyone in the world would be saying “Can you tell what it is yet?” I’ve considered what the steps would be, how long it might take, and the network that would be needed to support and disseminate the findings. I call it DISC: Decipherment and Impact of a Signal of Content.