I've held many consulting positions while working on this blog but now I have one that includes 4 hours of commuting each day, meaning that most of my non-working life is put on hold for the weekends, especially during World Series week. Typically I work on this blog on weekends, but I cannot do that and have the rest of my life. So I think I'll take a break. After 5 years and a book I've covered a lot of ground. In this post I'm putting a bit of what I learned into scenario form.
As I see it there were several stages in speech origins. The first was a long period of vocalizing in which emotions were shared but not named. Then came a word/phrase period, followed by true sentences (subject + predicate). These first languages were likely very concrete and only later developed metaphorical and abstract capabilities.
Vocalizing probably began around 3.3 million years ago when, according to louse DNA information, our bodies had become hairless enough to support two distinct forms of lice. (see: Lousy Timelines) Hairless primates have a problem because they cannot form social bonds via grooming and their young cannot hang onto their mothers' hair. Robin Dunbar and Dean Falk have done good work in this area. Falk especially has analyzed the development of vocalizations that are not words.
As to why we became hairless, I don't know. I don't know why we are bipedal either, but balding mammals are not unknown in African woodlands. Elephants, rhino, and wild pigs also have little hair. Presumably the process of losing hair was accompanied by the counterprocess of making up for hair's disappearing social benefits. Mothers and infants maintained contact vocally while the mother put the infant on the ground. Adults vocalized together while grooming faded.
A vocalization period persists to this day in infants and is generally seen as a movement toward speech, but that goal may reflect the prejudice of speakers. A great deal of emotional development goes on during this vocalizing and the process needn't look to future language for justification. Myself, I suspect that there was a period of more than a million years during which the human lineage had its own distinctive birdlike nature—no flying, but plenty of chirping.
The vocalization-only period began when the lineage was likely some species of Australopithecus and ended after the rise of the Homo genus. This critical period saw the emergence of the African savanna and our lineage's adaption to the new environment. One important adaptation was the formation of cooperative communities, something very rare amongst mammals who are more given to herding and forming hierarchical societies whose members are unwilling to share what they know. On the open plains, however, slow, weak humans have no hope of survival in herds or even the more complex ape societies. They stood together or went extinct.
The oldest Homo known are about 2.7/2.8 million years old and sometime after that members of the lineage began using their vocalizations to name things. The first words were probably formed by random associations. I've seen infants in their first year do the same thing, making what I call "toy words" by themselves. Most such words fade, but a few are picked up by the family. I seem to recall a baseball player in the 1960s and 70s named Boog Powell and, supposedly, the nickname Boog came from a word he had used as a baby.
The critical step in the word origin was not the association of sound with thing—that's pretty much inevitable with a brainy species doing a lot of free form vocalizing. The key lay in others being willing to repeat somebody's association, and that willingness comes only when individuals are already motivated to share knowledge. Once word sharing had begun, Baldwinian evolutionary processes would support the development of an instinct to learn and use each other's words.
The critical evolutionary step was the rise of a cooperative genus and not some new semantic or syntactical intelligence. Apes are already able to associate a number of hand signs with specific things and focus their attention on a named object. What they needed was a reason to make use of that capacity.
How much more did Homo biology have to change once the lineage got to that point where it could name things?
One step was discussed in last week's post, the ability to combine two phrases into a whole. Apes cannot do this, and the reason is not hard to grasp. Two distinct phrases—e.g., that red ball and a blond lumberjack—direct attention in two separate directions. But we can combine the two by finding a common verb that unites them: a blond lumberjack kicked that red ball. So that seems to be an intellectual power that we have and apes do not. Our thinking in this regard is not just a scaled up ape ability; it is something new. Language, as we know it today, reveals a discontinuity between humans and apes.
From time to time I read a paper or get a comment saying that discontinuities in biology are impossible because evolution works in small steps, but today's world is full of such breaks. An obvious example is in the world of birds. They have a complex evolutionary history related to the dinosaurs, but the dinosaurs are long dead so when you look at the world today there is a huge discontinuity between birds and other animals we see. Similarly, the intense group selection that was part of the evolution of the human lineage appears to have left us without any race that can speak phrases but not sentences.
There is, however, an equally important continuum from words to phrases to sentences. The evolutionary process has not led us away from the early association between words and attention toward some more abstract syntactical and semantic processes; it moves in the opposite direction—toward more elaborate powers of attention.
When the transfer to full sentences occurred is uncertain. Last week's post noted a possibly relevant genetic doubling 2.4 million years ago, so we can put that as the earliest possible date (and frankly I don't believe the lineage was even using words back that far). Archaeological evidence puts the possible date as early as 1.8 million years ago when Acheulian axes first appeared. These are the first bifaced tools in the record, meaning both sides of a chopper have been worked to form a cutting edge. To make the axe, an artisan must be able to hold two points of attention in mind at the same time. If you are smart enough to join two sides of a stone by making an edge, you may be smart enough to join two phrases with a verb. Let's say that by 1 million years ago Homo erectus was speaking full, concrete sentences. I don't think it could be much later than that.
There is, of course, a big difference between the ability to speak about concrete things and what modern language can achieve. Is that all the result of cultural evolution? I doubt it. I think in particular some biological change was necessary to support metaphors and perhaps abstractions. Whatever that took, I figure that the biological determinants of modern language were in place by 150 thousand years ago. Although some people still date language as recently as 60 thousand years ago, my 150 K date is reasonably orthodox. There are quarrels over whether anything came earlier or if language sprung de novo out of a 'great leap forward' [i.e., a genetic mutation] of some kind. I'm firmly in the long-history camp.
I defend my position by noting the way we put abstractions and metaphors into concrete form. If we began right away using abstract symbols, I doubt that we would have organized abstractions so insistently in perceptual space, as every language on earth does. Instead, I think language would have a much more mathematical flavor. With something like Dirac's equation we can calculate quantum physics outcomes without having any perceptual understanding of what is going on. That means we cannot discuss the results meaningfully in ordinary language. Physicists talk about superposition, collapse, and entanglement but nobody can explain those terms. The reason for the failure is clear enough. Language organizes things according to a perceptible space; Dirac's equation does not.
A good discipline for anyone interested in writing is to try to write a purely concrete paragraph that hangs together. The tone tends toward that of a hard-boiled crime story for there are no abstractions or interior goals. Emotions are external. Someone can shake but not feel fear. There are no motives, only actions. Without metaphors we can never get into somebody's head or heart.
Metaphors are often defined as a "figure of speech" that says one thing is another thing. When it came to the honor of France, General de Gaulle was a lion in defense of his pride. There is a metaphor (and a pun too) used figuratively. You could just as easily say he was "like a lion in defense of his pride," turning the figure into a simile. But there are some metaphors that cannot be deflated. Her flirtatious behavior shattered his trust. Here the metaphor is shattered and no non-metaphor can be substituted.
Why not? Because trust is a psychological state, not a concrete thing. We can substitute a concrete thing for trust. We might belong to a culture that locates trust in the heart, so we could say shattered his heart but now we've replaced a metaphor with a metaphorical phrase since a shattered heart cannot be taken literally. Instead of calling this sort of phrasing "speaking poetically" we might say the user is speaking psychologically, for there is no way to talk about subjective psychological states without using metaphors (or, if you happen to be a professional psychologist, empty jargon).
How do we understand metaphors of subjective experience? In my own case it seems to me that the word directs my attention to my own knowledge of the experience and if I have no acquaintance with some subjective experience I don't know what the metaphor is about. As I have gotten older, much literature has become more clear to me.
Autistic people are reported to be baffled by metaphors, suggesting that there is some biological contribution to understanding them. Perhaps they cannot direct their attention inward. Naturally there is more to autism than understanding metaphors and I'm not suggesting Homo erectus was autistic.
Wherever metaphors come from, they allow us to speak of invisible things as though they were part of the concrete world. In fact, many people don't even realize they are using language in a way that demands interpretation rather than literal acceptance. I have spoken to many people who get indignant when I point out that nobody takes the Biblical reference to God hardening pharaoh's heart literally. Pharaoh's heart did not literally become like a rock or something. Yet language treats it as though and to understand that statement you have to know the feeling of a "hardening heart." It is not the feeling of a heart attack, but something else.
A second feature of modern language not present in concrete speech is the use of abstractions. We live in a world of abstract references. To take an example almost at random, look at Paul Krugman's column in the New York Times last Friday. Here is a purely abstract sentence (for emphasis, I'm putting all the abstractions in blue).
So a crisis brought on by deregulation becomes a reason to move even further to the right…
You have to be pretty comfortable with abstract words to follow that clause, and yet it feels almost normal because of all the structural components that give it a concrete context: brought on by, becomes, move even further. I can imagine some verbose Home erectus saying something similar: So a rainstorm brought on by dark clouds made us move even further into the cave. Thus, we have the paradox of organizing very modern ideas using verbal structures that may have been recognized a million years ago.
Whether this rise in abstractions required a biological change is uncertain. I have the impression that the change has happened so recently that it is essentially cultural and depends heavily on intensive education. Until very recently many abstractions were dealt with mythologically, presenting ideas in the form of living spirits. But there may be a biological component to the process as well. If there is, it was likely added a while back since everybody in the world today can speak of abstractions like justice, freedom, and rights.
The relation between perception and language is not news. The oldest advice given writers is Show; don't tell. In other words, make it as concrete as possible. Now that I have spent five years focusing on the origins of speech, it makes perfect sense to me, and I will end this period of maintaining my blog with a passage from my book that sums up what I have come to understand about language. Because of language we are presented with
a true biological novelty: a cooperative species able to share perception of a topic by directing attention with words. It is almost as though our lineage developed a new sense, a cooperative sense that for the first time let individuals know what another sees, hears, or even feels.