A Civilized Threshold

We live in a complex civilization, as diverse and innovative in its own way as the living world, explosively so, von Neumann might say. Somewhere in the many generations between our primate ancestors and ourselves, human culture crossed its own threshold of complication. The balance of this chapter will try to pinpoint the location of our threshold, using what we have learned about the RNA world as a guide. Many would claim that speech is our secret sauce, but speech by itself was insufficient; we did not cross our threshold until we became literate.

What is it like to live in a human culture that lacks writing? Between five and ten thousand years ago every member of our species, creatures biologically identical to you and me, lived in this kind of culture. And prior to the colonial era of recent centuries, there existed thousands of human groups whose contact with the civilized world was so limited they lacked not only writing but even the concept of writing. “There have been whole communities, whole cultures,” says linguist Roy Harris, “which did not know—and scarcely could have imagined—what it is to be able to write.”51

Despite the pervasiveness of written texts in the world we inhabit, literacy has been a comparative rarity in the cultural trajectory of our species, an outlier in terms of numbers but hegemonic in terms of power and influence. “Of the thousands of languages spoken at different periods in different parts of the globe, fewer than one in ten have ever developed an indigenous written form,” says Roy Harris. “Of these, the number to have produced a significant body of literature barely exceeds one hundred.”52

Imagine a world in which everything you and your family and friends know about history, nature, and practical skills is learned through personal interaction, through what Jack Goody and literary historian Ian Watt call “a long chain of interlocking conversations between members of the group.”'’3 In this world all knowledge is internalized by individuals and lost through death and forgetting. If you want to know about some event that happened last year, or about the utility of a particular plant, or about the nature of the lands beyond your immediate territory, there is nowhere to turn except to the fallible memories of others.34

And if you desire exposure to the sequences of speech, you strike up a conversation. “It is often hard for the literate world to remember that the core ecology for language use is in face-to-face interaction,” write linguists Stephen Levinson and Judith Holler. “This is the niche in which languages are learnt and where the great bulk of language use occurs.”53 At its root, human speech is time bound and space bound.36

In this world, you never ask how to pronounce a word because you never encounter a word except as it is pronounced. You never know how to spell a word because there is no alphabet. You never have your grammar corrected because standardization is unknown. There is no confusion between “your” and “you’re.” You don’t even possess the concepts of word or sentence because constructing a grammar, parsing the sequences of the speech stream, is a profoundly literate activity. “Pre-writers had no such concepts,” insists psychologist David Olson.57

The affordances available to you in this world are limited. Your perception is restricted to what your naked eye can see, and your power to manipulate the physical environment is limited to what your hand can hold or your back can carry, or what you might convince or coerce another person or group to do on your behalf. In this world, our ancestors had the same capacity for spoken language that we do. Their bodies were as strong as ours and their brains just as big. Their thumbs were opposable and their grips just as versatile. Their vision and hearing were as acute as ours and their taste buds just as sensitive. So why did they use flaked rocks for tools while we transplant hearts and land space probes on comets?

Throughout the living world, more complex behavior always seems to require more complex animals or animal societies. How, then, did human culture become more complex and sophisticated without a parallel need for increasingly intelligent and creative individuals?58 The answer, as Freeman Dyson writes, is that “beyond a certain point, you don’t need to make your machine any bigger or more complicated to get more complicated jobs done. All you need is to give it longer and more elaborate instructions.”59

In this we see parallels to von Neumann’s self-reproducing automaton. For the universal constructor to build a more complex automaton, all that was needed was a more complex set of instructions. Human culture, though, is less like construction and more like configuration. We the people are constructed, of course, by our biology. Once born, however, we are configured by our culture, our unique set of input sequences.

For human culture to cross the threshold, major improvements were needed both in our sequences and in us, their interactors. As with the RNA world, crossing the threshold required the addition of sequence storage with greater capacity and stability and more reliable replication, plus more powerful, flexible, and selective interactors, our equivalents of DNA and protein. Writing gave us a stable, versatile, and cumulative storage and replication medium for the sequences of speech, a medium that made random access possible. Equally important were measuring instruments that extended the range of our perceptual systems, and sophisticated tools and machines to amplify and extend the power of the human body, especially the hand.

Few archaeologists or anthropologists would quibble with the importance of these factors in the transition to civilization,60 but this is less about Neolithic history than about how improvements in sequences and interactors can explain the evolution of complexity more generally. As we witness human culture crossing its threshold of complication, we sense echoes of the way living systems crossed their own threshold billions of years ago. That is because the limitations which restricted the scale and complexity of preliterate human culture are the same limitations that kept a lid on the evolutionary potential of the ancient RNA world. The creative benefits conferred upon humans by writing, measuring devices, and technologies of manipulation are the same benefits conferred on the RNA world by adding DNA as a storage/replication medium and proteins as enzymes.