The first [question lying behind my work] is, why is language as it is? Mankind could have evolved an enormous number of different semiotic systems; why did they evolve a system which has these particular properties that language has? – M.A.K. Halliday
I have been reading a series of interviews with the Australian linguist Halliday and I ran across the above passage. Derek Bickerton asks this question as well. So it crossed my mind to see how far along I have come on this blog to answering it.
New functions, of course, do not evolve out of nothing. They take what they have and build on it. In language’s case it is plain that one of the things we took is the vocalization system that already existed in mammals generally and primates particularly. Apes do a lot of screeching. We kept up that part, but at the same time we tightened our controls over the sounds we make. We got rid of the ape air sacs that make sounds louder but less distinctive. We gained a finer control over our tongues. We developed the ability to prolong our exhaling without becoming giddy for lack of oxygen. These sorts of things are all routine evolutionary adjustments and carry few theoretical surprises. If they comprised the whole story, there would be precious little reason for language’s exclusivity. All apes would be talkers, having long ago adapted their vocalizing apparatus. Yet that did not happen, so there needs to have been some sort of trigger, a reason to adapt vocalizing beyond the limits reached by apes.
The benefits of language seem clear enough. Speech helps organize group efforts. A further benefit is the rise of traditions that pass hard won knowledge to new generations. Yet there must be more, or else apes too should be talking. Wouldn’t chimps benefit by being told, “I saw leopards off to the left and ripe mangos to the right”?
The problem with any group benefit is the greedy individual. That’s the guy who takes what the group provides and keeps his own discoveries to himself. If he is warned of leopards to the left, he goes right. But if he knows of mangos to the right, he keeps the secret to himself and lets the others wander as they will. The greedy guy has a slight survival advantage over those who share, and in evolution a slight advantage is all it takes. Over the long run, the greedy guy’s genes will out, so silence prevails.
There is, however, a case where silence does not benefit the greedy. That’s when individuals are so interdependent that they hurt themselves when they by hurting others. They cannot afford to let others stroll toward leopards even if stopping them means getting fewer mangos. This kind of development is very rare in the biological world, and tends to come late along an evolutionary trail. The most familiar example are eusocial insects like termites, ants and bees. From a mammalian perspective, they are very old, but by insect standards they are new boys on the block. They are also extremely successful, accounting for much of the world’s insect life and having found niches around the globe. They too share a great deal of information that makes cooperation much easier. Humans too are recent mammals who depend on one another for mutual survival. In such a situation, communication is not just tolerable; it is a necessity.
At the same time, the ability to tell strangers apart becomes important. Grasshoppers needn’t worry about friend or foe distinctions. No other grasshopper is a friend. Ants, however, need to spot their enemies. Ants from other colonies do not smell right and are put to death. Humans live more subtle lives and may not put strangers to death, but they still need to distinguish the trustworthy tribal members from the outsiders. A big clue comes from language, like the famous biblical tale (Judges 12) in which enemies were spotted by their inability to pronounce the Hebrew word shibboleth. This being a bible story, those who could only say sibboleth were killed. Another biblical example is in the Gospels (Matthew) when a serving girl in an inn says surely Peter is a follower of Jesus as even his accent gives him away. The advantage of telling friend from foe is probably one reason most all of language is not hard wired in the brain. People can hear the strangers among them and (at the tribal level) know who is trustworthy enough to be told a secret.
And what secrets shall we share? When language was new and taking its basic shape, the richest form of knowledge enjoyed by these suddenly talkative apes was perceptual. They recognize shapes, sounds, and scents. They can see threats and opportunities, and they can navigate their way through space, so the most powerful way to structure language among a group of trusting apes is to share perceptions. If I saw mangos off to the right, I can share that knowledge by saying mangos and pointing. In this way I am directing another’s attention in a particular direction and introducing a topic. The role of attention in language is more controversial, but on this blog meaning comes from directing attention and syntax provides a way of shifting attention while holding several focal points of attention together. Once language got rolling, abstract ideas could be expressed as well, but they are expressed as perceptions. Your infidelity has shattered my trust in you. Infidelity and trust are both abstractions, yet they are expressed as objects in space that can act and be acted upon.
So why did we evolve a system with the properties of natural languages? Given the fact of vocalization and interdependence, we overlaid the sound system with a way of sharing attention and the perceptual knowledge it brings. This communication system never hardened into a hereditary system, as it did among eusocial insects. Over the long generations, language became more elaborate and powerful than it was for the first talkers, but the foundations of culture, community and a perceptual way of knowing are still built into our primary means of communication.