At the heart of our unique language ability lie other forms of cognition and cooperation, argue Paul Ibbotson and Michael Tomasello.
The natural world is full of wondrous adaptations such as camouflage, migration and echolocation. In one sense, the quintessentially human ability to use language is no more remarkable than these other talents. However, unlike these other adaptations, language seems to have evolved just once, in one out of 8.7 million species on earth today. The hunt is on to explain the foundations of this ability and what makes us different from other animals.
The intellectual most closely associated with trying to pin down that capacity is Noam Chomsky. He proposed a universal grammatical blueprint that was unique to humans. This blueprint operated like a computer program. Instead of running Windows or Excel, this program performed “operations” on language – any language. Regardless of which of the 6000+ human languages that this code could be exposed to, it would guide the learner to the correct adult grammar.
It was a bold claim: despite the surface variations we hear between Swahili, Japanese and Latin, they are all run on the same piece of underlying software. As ever, remarkable claims require remarkable evidence, and in the 50 years since some of these ideas were laid out, history has not been kind.
First, it turned out that it is really difficult to state what is “in” universal grammar in a way that does justice to the sheer diversity of human languages. Second, it looks as if kids don’t learn language in the way predicted by a universal grammar; rather, they start with small pockets of reliable patterns in the language they hear, such as Where’s the X?, I wanna X, More X, It’s a X, I’m X-ing it, Put X here, Mommy’s X-ing it, Let’s X it, Throw X, X gone, I X-ed it, Sit on the X, Open X, X here, There’s a X, X broken … and gradually build their grammar on these patterns, from the “bottom up”.
If not universal grammar, then what? We know language uses a lot of mental processes that are not unique to language, such as memory, categorisation and forming analogies. For example, when a child says, “We holded it,” they have made an analogy to past tense verbs with the regular -ed ending. These kinds of mistakes give us vital clues to the mechanisms children are using to build their language.
Acknowledging that much of language uses the same process as the rest of cognition, a new branch of linguistics has developed from those principles. This can’t be the whole story, however. The limitation of this approach is that although these processes are not unique to language, they are not unique to our species either. For example, chinchillas can form categories based on speech, yet clearly lack anything like human language. So what is going on?
Putting our heads together
It might be that general cognitive processes such as memory and categorisation are necessary, but not sufficient, for language. For a string of sounds to be understood as language, something else is needed – Chomsky knew this, and his proposal was universal grammar. There is exciting new evidence showing that this “something else” is a broader adaptation for culture and cooperation. This brings us right back to the original question of our place in the natural world. We share similar but different histories from our evolutionary relatives, the chimpanzees. Why is that we can understand language and acts of communication, such as pointing, and they cannot?
Understanding communication requires a deeper understanding of how humans work – their intentions and, specifically, their communicative intentions.Chimpanzees just don’t share this level of understanding. Chimpanzees and other great apes can discern what someone is intending to do when she pursues a concrete goal, like obtaining a banana, but they cannot discern what someone intends them to pay attention to or to think, which is the purpose of communicative intentions.
Importantly, these same basic processes of intention-reading are necessary not only for language, but also for discerning what someone is communicating when they simply poke their index finger out in a particular direction for the purpose of communication. To understand why someone is pointing to, for example, a bicycle leaning against a tree, one must share some background experience and knowledge with that person to determine why on earth they would be directing one’s attention to this particular situation at this particular moment.
The idea is that something (we don’t precisely know what) in our evolutionary history placed pressure on us (but not chimpanzees) to evolve the kind of mental machinery that allows us to read communicative intentions. One of the consequences of this was that it provided a key mental capacity for language. But it also put in place the potential for us to take part in ever more complex and large-scale cooperative ventures that form the fabric of our different cultures.
The place of language
So in some ways, saying language is unique is stating things the wrong way around. Language is not the unique thing in itself – it is an expression of what is unique: the ability to put our heads together and collaborate. Language is our species’ party trick, akin to the octopus rolling up like a coconut. Unlike the octopus, humans’ unique adaptation caused a profound cascade of consequences for our species, the full breadth of which we are still grappling to understand.