The feature article in Scientific American (subscription required) this month addresses the role that flint knapping (the practice/art of making Stone Age tools by striking one rock against another) might have played in the development of the human brain, language, and even teaching. (And here’s a related article in Nature if you prefer more academic prose.) Here’s the gist.
The basic idea that toolmaking shaped the human brain is not new. It’s at least 70 years old and ascribed to anthropologist Kenneth Oakley in his book Man the Tool-maker, though one might observe that the notion of homo faber is centuries old. It was discredited among behavioral scientists in the 1960s when it was observed that nonhuman species also used and even made tools. As the article recounts, “As paleontologist Louis Leakey put it in his now famous reply in 1960 to Jane Goodall’s historic first report of chimpanzee tool use: ‘Now we must redefine tool, redefine Man, or accept chimpanzees as humans.’” In abandoning tool use, behavioral scientists turned to complex social relations. Without putting too much pressure on a single sentence, one can see some of the difficulties here. First, why would tool use have to provide evidence of human cognitive exceptionalism in order for it to play a role in our cognitive development? That is, why would the fact that other animals use or make tools serve as evidence against the role of tools in forming our brains? In fact, wouldn’t it work the other way if we could see this effect across species? Second, why would tool use and “complex social relations” be exclusive rather than mutually reinforcing parts of an explanation for human cognitive development? That is, the discovery of better tools puts pressure on (and facilitates) the formation of more complex social arrangements in order to use those tools, which leads to further tool development, and so on: and all of this shapes human cognitive development. We certainly see that in the Industrial Age.
The research referenced above takes up a view like this and links the practices of experimental archeology with neuroscience. Experimental archeology is essentially the effort of archeologists to learn ancient methods through trial and error. In this case, it means learning how to flint knapp. What’s added here is neuroscientific study of the experimenters’ brains to see how learning to knapp affects them. Anyway, to make a long story short:
the toolmaking circuits identified in our PET, MRI and DTI studies were indeed more extensive in humans than in chimps, especially when it came to connections to the right inferior frontal gyrus. This finding became the final link in a chain of inferences from ancient artifacts to behavior, cognition and brain evolution that I had been assembling since my days as a graduate student in the late 1990s. It provides powerful new support for the old idea that Paleolithic toolmaking helped to shape the modern mind.
However, the research has some further suggestions. It’s certainly possible to learn knapping independently, through trial and error, learning from others through observation and imitation makes it a lot easier. One can imagine a small group of early humans creating tools and learning new techniques simply through observation. Then, at some point, one sets upon the notion that one could intentionally demonstrate a technique to another for the purpose of that other person imitating the first. That’s teaching. Needless to say some symbolic behavior could come in handy here as well. And that’s the speculation that ends the article:
The results of our own imaging studies on stone toolmaking led us recently to propose that neural circuits, including the inferior frontal gyrus, underwent changes to adapt to the demands of Paleolithic toolmaking and then were co-opted to support primitive forms of communication using gestures and, perhaps, vocalizations. This protolinguistic communication would then have been subjected to selection, ultimately producing the specific adaptations that support modern human language.
I’ve written about the notion of paleorhetoric a couple times here. It also comes up in The Two Virtuals. I think this issue is an important component of a new materialist rhetoric. Why? Though I find value in the speculative investigation of nonhuman rhetorical activity that typifies much current new materialist rhetorical study, I believe it is important for us to be able to see rhetoric as an ecological phenomenon in which humans and nonhumans co-participate. It is possible and often useful to cut the world at its joints and say “here’s human rhetoric” and “here’s nonhuman rhetoric,” but what we see here (possibly) is the emergence of symbolic communication among humans in the rhetorical encounters among people and rocks. It’s not just human rhetoric or human language.
And perhaps most importantly, rhetoric was already at work. The expert knapper learns to address his/her strikes of the stone: the angle and the force. One must conceptualize and plan. This is clearly composition, as we know composition has never been only about writing. However it is about expression in a medium. It is instauration, as Latour would put it. Perhaps, gentle reader, you are reticent to call this rhetoric, but we certainly seem willing to call it art, right? The art, and artifice, of flint knapping? Why do we find it easy to imagine art without rhetoric? Yes, no doubt, we could say that rhetoric is a kind of art. And when by rhetoric we mean the specific oratorial practices taught to young Athenians that would make sense. But when we think of rhetoric ecologically, as the capacity for expression and incorporeal transformation that arises in the relation among humans and nonhumans, it is more than that. Certainly, when a paleo human struck one rock with another that was hardly an “incorporeal” expression. And you can spend all day turning big rocks into smaller ones, expressing personal frustration or perhaps as punishment. But if you strike one rock against another until something that was a “rock” becomes an “axe” then you’ve done more than exert simple force. Those repeated blows have also incorporeally transformed that second rock. Its relation to the knapper has changed, and new capacities have emerged. Instead of a person with a rock we now have a person with an axe. In other words, it’s not just the rock that has been incorporeally transformed; the human has as well.
This is what new materialist rhetoric is (at least partly) about: understanding how the relations among humans and nonhumans shape capacities for thought and action.