5

HUMAN BEING

Another Forest

On another continent, halfway round the world, a forest emerges from farmland in Rwanda, central Africa. You walk in through a mix of broad green leaves, which gives way soon to dense bamboo. Stands of tall stems all lean one way, then another.

The walk is a climb. The bamboo gets skinnier, accompanied by stinging nettles. Soon the path is winding through vague, overgrown green shapes. Eventually, our guides point them out: mountain gorillas. Huge animals, black against the forest’s green.

These first ones we saw were part of a large family group, named Igisha, of nearly three dozen. Mountain gorilla groups often have several related adult males, “silverbacks,” with one of them dominant. Together with them will be various adult females who won’t be closely related to one another, some number of younger males and females, along with children of various ages. A group has its own home range, with a rough core area and a periphery. These territories are not strict and can overlap, but different groups avoid each other.

The adults are massive. When a male stretches out a single arm, it is truly, eye-wideningly, huge. But when all is well in the group, the atmosphere seems to be one of gentle, low-key affection.

The group we visited on this first encounter was scattered, with some on the ground and others wandering in suspended patches of the low canopy. On our second trip up the mountain, we came upon a group of about five sitting together, quite close. A male on the ground kept an eye, quite carefully it seemed, on youngsters climbing overhead.

There we are, a small, quiet clump of humans and a similar-sized group of gorillas. We are all primates, apes. We share a great deal of history and a lot of DNA, but are obviously different, with clothes and cameras on our side, and journeys that brought us here from all over the world.

The gorillas want nothing from us. They show occasional interest, sometimes move past us very close. But we hardly matter. They steadily strip leaves, take apart stems and branches as we watch—a continual stream of fresh green food. On each visit we are allowed to be with the gorillas for an hour, exactly, and then we say something like a silent goodbye and walk back down the hill.

Looking back up into the mountains from below, near the end of the walk, I see great humped forms. Some of those overgrown green-canopy shapes now look like huge gorilla bodies bent over, as if the whole forest is expressing their presence.

Culture

Mammals arose back in dinosaur-dominated times. But most of the great mammalian enterprises unrolled after the mass extinction that ended the dinosaurs’ reign on land. During our time with songbirds in the previous chapter, we looked at some groups that branched off from the rest of their part of the genealogical tree quite early, wound tenuously through the epochs, and led to just a few surviving species today. The same is seen with mammals. The monotremes—egg-laying mammals, the platypus and echidnas—are an early-splitting group with just five species (or fewer, on some counts) alive now. Another early branching led to marsupials, such as kangaroos, on one side and the much larger collection of eutherian (or placental) mammals on the other. As with songbirds, Australia is where many of the present survivors of these ancient offshoots have their home.

Within eutherian mammals, primates are one of the groups that appear in the fossil record soon after the mass extinction, though they might have been around a while before that, living inconspicuously in the last days of the big dinosaurs.

One branch within primates is the great apes, or hominids, dating from some 15 million years ago. The term “hominid” has changed its meaning; it used to refer just to us and a few very close relatives, not to gorillas and the like. Now it is used for a larger cluster, which includes gorillas, chimps, bonobos, orangutans, and us, along with extinct species on the same branch. Within this cluster, our closest living relatives are chimps and bonobos, followed by gorillas, with orangutans a little further away.

These relatives of ours, the other great apes, are forest animals. They are generally quite social (with orangutans much less so). But sometime over 5 million years ago, a primate line made its way out of the forests onto the African savanna. There, these adventurous apes began to form more complicated, integrated societies.

The human form of social living is special among animals, as it includes collaboration among large numbers of unrelated members of the same species. Even the tolerance seen in humans is unusual, at least among primates. The primatologist Sarah Hrdy offers a memorable thought experiment in which, on a crowded commercial flight with hundreds of unrelated people crammed together into a metal tube, she imagines how things would go if the passengers morphed into a collection of chimps. “Any one of us would be lucky to disembark with all ten fingers and toes still attached.” Not every human flight goes smoothly, but body parts tend to remain with their owners. Many fish would probably do better than chimps. Don’t try it with octopuses. Human getting-along is a step outside the ways that close-up living works in many animals, especially our nearer relatives.

Our tolerance of strangers (such as it is) and willingness to collaborate with others required changes at the level of individual psychology, but the feature of human life that I want to emphasize more than any other in this chapter is the role, and rise, of culture. I intend that term in the broad sense that is used in biology and anthropology—culture is not just Beethoven, though we get there eventually. Culture in this sense refers to the establishment and development of ways of behaving that are passed from generation to generation, and sideways within a generation, not through genes but through watching and imitating, learning and leading, and (sometimes) deliberate instruction. Cooking food, wearing clothes, rules that prescribe who you can and can’t marry—these are all aspects of culture in this broad sense.

The cultural spread of behavior can begin with just one individual watching and imitating another who is doing something that seems to work. But this passing on and passing around of habits, rules, and techniques can become more organized, based on communication and ritual. It comes to include “material” culture—the fashioning and use of tools that become standardized, and the deliberate transformation of the local environment. Eventually, societies produce objects, marks, and social behaviors whose overt role is to consolidate and carry patterns of behavior forward: “This is how we live.”

Culture not only consolidates behaviors but also gives rise to a new kind of change. As behaviors recur—are imitated, encouraged, and taught—they can also be slowly improved. Details can be refined, and one technique or habit can be combined with others into a useful sequence or chain. If a small innovation spreads (a better way of weaving, for example), it becomes a platform for more experimentation. Human behavior becomes a mix of individual tinkering and persistent cultural tides.

Within these culturally embedded forms of learning, a special form is what Kim Sterelny (the philosopher deceived by a lyrebird in the previous chapter) calls “scaffolded” learning. Individuals of one generation, through their actions, encourage the learning of particular skills or ways of thinking in the next generation. This is not just learning by imitation, but learning that is actively aided by others. For Sterelny, human societies continually rebuild the social and material scaffolding that children rely on as they grow up. This creates a “looping” pattern within a culture, a loop between the actions of those who are already present and the experiences of new arrivals, who then continue the practice. An example of scaffolded learning is apprenticeship, acquiring skills by watching, helping, being taught by someone who knows them well. Human upbringing involves a lot of apprenticeship, even where it’s not obvious. Sterelny’s book on these topics is called The Evolved Apprentice—the title summarizes the picture. Scaffolded learning is not common in animals. There are a few species whose mothers teach some skills, but this is an area where humans have become different.

When did culture start to take on this role in our ancestors? The anthropologist Joseph Henrich, whose work I draw on often in this chapter, thinks that it happened gradually, but included a transition he describes as “crossing the Rubicon”—reaching a point of no return. At this stage, it becomes hard or impossible to get by without culture, and from here its role only increases. (The Rubicon is a river that Julius Caesar crossed in 49 BCE during the early stages of his revolt against the Roman republic; after this crossing, turning back would be pointless, and the only sensible choice was to march on to Rome.)

The picture to have in mind here is not one with a single species, our species, taking the step. Henrich suggests a date of around 2 million years ago for the point of no return. That is early in the history of our genus, Homo, and before the appearance of our species, Homo sapiens.

Until recently, researchers tended to think in terms of a pretty sharp divide between humans and all other living animals with respect to this feature. Social living of various kinds is common, but the kind of information sharing seen within culture was regarded as almost nonexistent in nonhuman animals. Now this looks wrong, with a growing list of culturally learned behaviors in other animals, especially chimps but also many others. The lyrebirds and bowerbirds of chapter 4 are both examples—lyrebirds with their song repertoires, and (probably) the bowerbirds with their decorative styles. Even bees show simple forms of cultural learning. The question of why other animals lack culture has now been replaced by a different question: Why did it take off and become so elaborate in humans, while remaining a minor element (hardly noticed at all for a long time) in other species? Is it due to brainpower, or perhaps a more cooperative style of social living that was already in place in our lineage, a style of living that made culture especially useful and encouraged its early sparks?

That last question is unresolved, though I’d put some stock in the idea about cooperation. More generally, we can see culture as bringing together several of the forms of action that we looked at in the last few chapters. Culture nearly always involves social interaction (though you might watch, and copy, secretly). Once we get beyond its simpler forms, it tends to involve engineering—making and reshaping, “material culture” as I called it a moment ago. Before long, some parts of material culture are made for purposes of social interaction; they are made to aid ritual, and cultural memory. And though we can imagine a narrowly practical way this all might go, in fact it seems to have involved a great deal of display and evaluation. Culture brings those older forms of action together, and it augments them, makes them more powerful.

Living in social situations of this kind leaves a mark on our psychology. One example of this involves a very interesting behavior, also perhaps a disconcerting one. The example involves the awareness of norms—awareness of how people should behave—in young children.

Children often seem to have an eye out for transgressions and violations in everyday behavior. This tendency seems a likely case of something that would need to be learned, probably through a fair bit of experience of social life. But a surprising series of results show that very young children appear primed to interpret various behaviors they see in terms of norms, and experiments keep pushing earlier and earlier the age at which this is seen.

One of the first papers looked at twoand three-year-olds. The children would watch someone do something that was new to them, playing a simple game with toys, and the demonstrator would do this new thing in a deliberate sort of way. When the children afterward saw a puppet do the new thing differently, they would spontaneously protest and correct the puppet. Two-year-olds issued commands: “Don’t!” Three-year-olds did this and also made normative protests: “It does not go like this!” They seemed primed to look for norms, and also to enforce them.

A moment ago I said I find this behavior disconcerting, but the way some of the experiments played out, with very young kids taking umbrage at the most arbitrary violations by others, does have a certain charm. Findings of this kind continued; even eighteen-month-olds do the same sort of thing. As some of the experimenters noted, it’s not surprising that very young children want to follow local norms and watch out for them in new situations; what’s surprising is that a three-year-old would want to enforce these norms in others. It had been known before this that children do have their eyes out for norms in contexts that involve helping. In the newer work, we see this extending to settings where there’s no helping in the picture. It’s all arbitrary—do you have to make the yellow block move by pushing it this way?

Does this mean that we’ve learned that looking for and enforcing norms are “in the genes”? No; just about everything in human development involves a combination of genetic and environmental factors, tangled together from the start. But we’ve learned that an ordinary developmental pathway for a human tends to give rise to this behavior without anything like the amount of instruction we might have thought necessary, and it appears very early. The behavior appears only in a particular kind of social context, and the kids do have to learn what is proper in their circumstances—do you push the yellow block with this thing or that one? But they will be inclined, without much prompting, to make a normative distinction of this kind and act on it.

In a case like this, we can also see the possibility of a sequence in which learning starts out heavily involved in some behavior and then its role gets reduced. In highly organized social setups, where it really matters that you get a sense of the right ways to behave, some things might start out being just about entirely learned, but if a genetic mutation pops up that can nudge the newcomer along, make the task easier, then that genetic change could spread. An attentiveness to distinctions between okay and not-okay behaviors, a tendency to interpret what you see around you in this way, could well be advantageous in a situation like this. As my language “nudge along” indicates, all this is liable to be a matter of degree; we might end up with a little bit of initial attentiveness to this feature of situations, and then a little more. Behaviors and habits that initially require learning can become more firmly set in the human developmental pathway. This is a way in which culture can infuse nature, and a way that human life tends to frustrate both sides of old “blank slate” versus “all in the genes” dichotomies.

In my sketch of the role of culture in human life so far, I have followed Henrich’s account quite closely. He emphasizes the development of useful knowledge, habits, and techniques. In fact, just about the entire story, as he tells it in his book The Secret of Our Success, is a story about the accumulation of devices and tricks, adaptation to difficult circumstances. Henrich seems in awe, and rightly so, of the knowledge seen in traditional societies throughout the world. He marvels at their ability to develop complicated methods for processing and detoxifying foods, methods that reliably work even though no one really understands why. People in traditional societies survived easily in environments that turned out to be impossible for well-equipped European explorers, who perished or turned back in despair, leaving a trail of well-attired bodies behind them as they retreated. When I talked a moment ago about a cultural “Rubicon” that was crossed, this difference between locals and intruders illustrates what Henrich has in mind. His Rubicon is a stage at which typical individuals being born into a society could not possibly learn on their own all the techniques and habits they need to stay alive, even if they wanted to. They have no real choice but to become part of the culture they find themselves in, and continue the process of absorption, transmission, and occasional improvement.

Not everything that becomes entrenched in a culture in this way is so beneficial. Mixed in with the accumulation of solutions to problems and fine-grained knowledge of conditions can be more destructive practices. Quite a few traditional societies invest a lot in practices involving the detection and punishment of sorcery. This can become a significant part of life and one with heavy costs. That is an extreme example, and other cases have more of an appearance of unhelpful arbitrariness. Given the nature of cultural transmission, it makes sense that any culture, traditional or modern, would end up with some practices that work well and others that have just gotten “stuck.”

In Henrich’s treatment of the growth of culture in human evolution, this unhelpful side is so far in the background that you wonder whether he thinks it exists much at all—or whether, perhaps, he thinks that cultures are so tightly knitted together that the highly effective parts cannot be pulled away from the elements that appear more costly or at least arbitrary. Some of the cases here are so intriguing. Tierra del Fuegians, living at the very tip of South America, traditionally made arrows by choosing wood from a tree whose branches are crooked, and laboriously straightening it. Each shaft was then pressed into a grooved stone and rubbed with fox skin. When feathers were added, right-handed archers should use arrow feathers from the left wing of a goose, and vice versa … We might read an account like this and think we can sort through which elements are useful and which are arbitrary preferences that became entrenched even if they did no good. Henrich’s message is that if we think we can do this, we are probably fooling ourselves.

Communication Again

Some of the cultural patterns that took root in early human societies would not require language. But language, when it arose, would have transformed just about everything.

The age of language, in evolutionary terms, is still unclear. It is probably older than our species, arising in at least some form back in the lives of earlier kinds of Homo. Many linguists through the twentieth century saw language as completely different from everything else that we and other animals do. This view was championed by the American linguist Noam Chomsky. He argued that language, in its central features, could not be something that came into being in small steps and slow improvements within social life, but must have arisen through a decisive shift on the internal side, a change within our minds.

This has come to seem unlikely in the light of work in a variety of fields, including anthropology, psychology, and animal behavior. This work has made a pathway to language that moves through gradual steps seem plausible. Gesture, rather than vocalization, may have been the main medium during some early stages. Gesture in some nonhuman primates is rich and complex even when vocalization is simple and inflexible. Language could become vocal after it had already achieved some of its distinctive features. The freeing-up of hands that vocalization enables certainly seems advantageous, and the transition might also relate to what was being said back then. In thinking about language origins, people sometimes imagine a sort of focused, one-on-one communicative exchange, but the paradigms of early human communication might instead have been more broadcast, exhortative, group-level: “HEY everyone! We’re going to do this, and then this … Let’s do it!”

In the previous chapter, I looked at communication in a general way, with the birds chattering away before us. I set out a framework based on sender-receiver interaction, the interlocking of behaviors “on each side” of signs and symbols. Communication is an interplay between production and reception, speaking and hearing, gesture and interpretation. Human language fits this pattern, but it has special features. I’ll discuss two, both of which are seen in faint forms in some nonhuman communication.

The feature of language that motivated the language-is-special view defended by Chomsky is syntax, or grammar. A language has rules by which basic elements can be combined, recombined, and recombined again, yielding an endless stream of new sentences, expressing things that have never been said before. Rather than a fixed collection of signals (eagle approaching), a language contains a collection of words from which new combinations can be continually formed. This open-endedness is central to the power of language, to its creative role both in social life and in our minds.

A simple version of this feature is seen in the dances of honeybees. These dances are built on rules by which both the distance and direction of food can be communicated when a foraging bee returns to the hive. This system is not creative in the way that language is, but it does have principles by which elements are spliced together. This is also seen in some kinds of primate communication, including more complicated alarm calls than the vervet ones in the previous chapter.

The second feature of language I want to highlight is one that bridges the social and psychological. Human language is based on a back-and-forth between senders and receivers, as usual. But the point of language, at least some of the time, is to connect the thoughts, the private inner states, of speaker and hearer.

Some very old views of language offered by philosophers emphasized this side. John Locke, in the late 1600s, saw language as a medium by which the privacy of our mental lives can be bridged. Each of us comes up with all sorts of thoughts from which others, as well as ourselves, might “receive profit and delight; yet they are all within his own breast, invisible and hidden from others.” Language, he said, arose to enable our invisible ideas to become publicly available.

From an evolutionary point of view, there has to be another step in the story. Speaking and listening can only arise and spread if they have practical benefits of some kind, if they help individuals make their way through life, help societies function, or both—it will probably be both. This means that language has to guide action as well as thought: that is where the rubber hits the road, in evolutionary terms. But it does seem that the way that language earns its keep in human life, the way it manages to call forth the effects that keep it around, often does involve its ability to connect the impressions, reflections, and musings of different individuals. Language use is, in a phrase from the philosopher Josh Armstrong, a form of “minded communication.” This is communication in which the linking of minds, as well as behaviors, is part of the story of how it works.

Some other primates show glimpses of minded communication. The use of calls and gestures can be guided, in some cases, by one animal’s sense of what has been seen or heard by another. These “audience effects,” where a speaker or sender does things differently according to their assumptions about the knowledge or preferences of the audience, is a first step down a road that leads from sender-receiver coordination to the revelation of our minds’ hidden contents.

Construction, Convention, Imagination

Some primates build platforms in trees to sleep on, but they are simple and temporary. Birds’ nests, in contrast, can be very elaborate. Weaverbirds, in Africa, are especially impressive. In Kenya I saw a city-like collection of intricate, globe-like nests suspended from branches over a stream. We don’t know much about shelters used in the earlier stages of the human evolutionary path. The artifacts whose history we do know well are stone tools.

The first evidence of stone tools dates from about 3.4 million years ago, though at this stage the tools may not have been actively shaped, just put to use if they started out suitable for cutting and scraping. Deliberately shaped tools follow, from perhaps around 2.6 million years ago, and toolkits had bone and horn added. From about 1 million years ago, fire was used as well. Earlier in this chapter, when I was introducing the cultural passing-on of behaviors, I mentioned the example of cooking. Cooking, as a behavior, is definitely not “in the genes”; it is learned and reproduced in the social environments that humans grow up in. However, in another sense, cooking is in our genes—it has left its mark there. The use of fire to cook food changed the evolution of our guts—they became smaller, for a start—and also our teeth. In a social environment where cooking is common, the genes that are favored differ from the ones that do well if food is always eaten raw. The fact that cooking is kept around by way of culture is beside the point.

The same is likely to be true of stone tools and our hands. The “precision grip” between fingers and thumb formed over 3 million years ago, before Homo, perhaps because manipulation had become important to our lives through the use of tools. Behaviors based in culture can feed back and affect genetic evolution.

The building of shelters during our early days might have been common, but if so, this practice didn’t leave much trace behind. There’s good evidence of the building of enduring structures from about 500,000 years ago (and scattered evidence from earlier), but I will jump ahead to a landmark, the oldest known group-level building projects that used stone on a large scale. These are found in present-day Turkey, the Göbekli Tepe buildings. They were occupied from about 9500 to 8000 BCE. The dates are important because, at least in the European and Middle Eastern context, this is a date before, or right around, the start of agriculture and settled communities.

The scale of Göbekli Tepe is substantial—hectares of stone columns that probably once supported roofs, decorated with carvings that endure. This large-scale building project did not, apparently, arise from settled society. That had been the usual assumption—that agriculture and food storage might prompt the first permanent buildings. The Göbekli Tepe buildings are old enough to raise the possibility of things going the other way round. They mark a major investment in religious and ritual practice, it seems, and would have required a lot of people. Perhaps a strong development of ritual life motivated a settling-down, in this case, and the beginnings of an agricultural society.

Much early settling-down probably did not involve buildings on anything like the Göbekli Tepe scale. A transition from a nomadic existence to agriculture and a settled life once seemed a natural example of human progress. Recent discussions have questioned this. Early farming would have been a precarious existence and, quite possibly, less appealing for the average person than a hunter-gatherer life. But a settled life with farming brings with it larger population numbers, also specialized soldiers and other enforcers, and this meant that agricultural communities could often dominate the environments where they settled.

Our picture of this transition—from a hunter-gatherer life to farming—has often been populated by stereotypes. The hunter-gatherer life has been portrayed as simple, also—on the positive side—as very egalitarian, while settling down brought with it a more complex and structured life. In fact, life without farming was diverse, sometimes settled and prosperous (especially on coasts), and saw a kaleidoscopic variety of social organizations. Discussion in Australia, where stereotypes about indigenous societies have been especially marked and also harmful, has seen a new appreciation of the rich complexity of these cultures in the millennia before European contact. It still appears true that the process of settling down and the growth of surpluses, whether achieved through farming or in other ways, makes new levels of inequality possible. Hierarchy and enforcement grow within everyday life.

The political scientist James Scott’s book on this topic has a chapter called “The Golden Age of the Barbarians”—a deliberately incongruous phrase, as we think of barbarians as unkempt, brutish types. What Scott means by “barbarians” is just people living outside of a settled state. (This was an old meaning of the term.) The passage to statehood runs, in each locality, through the twilight of a life that gradually becomes impossible as it is edged out by more organized, higher-density, more unequal living. (Here I assume that the transition is local and does not involve outright invasion, which is another way for things to go.)

Though there would be much diversity across places, and all this does depend on what you like, it may well be that the first time the average state dweller was better off than the average non–state dweller, or “barbarian,” in a lot of locales was many, many centuries later. I remember being amazed when I first learned that, in old hunter-gatherer skeletons, when an adult died, their teeth were often in pretty good shape, by modern standards, despite never having seen a toothbrush or a dentist for the whole of their lives. The teeth of people from early agricultural societies tend to be much worse. The average early farmer, living in a world of steadily accumulating sewage and tax collectors, dealing also with the first of countless waves of disease coming in from their domesticated animals, might have had good reason to look wistfully at the lives of the last barbarians, retreating from the fringes of their newly settled lands.

A medieval coronation ceremony is performed, and suddenly an individual acquires the ability to direct the movements of huge numbers of people. Whole states are set in motion, in one direction or another. If a different young person had been under the hands lowering the crown, masses of people would have taken a different path.

The phenomenon seen in the coronation is an extraordinary extension of a trend we have been following for a few chapters, a shift toward longer lines of control of nature, achieved through deliberate action. In human life, this trend is taken very far. The way this works is dependent on the details of particular circumstances and cultures, but a couple of general features of the human animal give it this capacity.

One is enormous social coordination, made possible especially by language. Another is psychological: the imaginative generation of plans, consideration of possibilities, the formulation of distant and novel goals. With this, action acquires a new kind of directedness, directedness on the merely possible, as represented in thought and language.

Back in chapter 3, I looked at a shift in the history of action from habit-based to plan-based choices. Rather than just going with actions that have worked before, a planner tries to model their situation, assess options, and choose the one that looks best. This will tend to be slower than relying on habit, but sometimes it is worth it. When it begins, this is a shift in the causal processes by which things get done in the world.

In the first discussion of goals and purposes in this book, in chapter 2, I distinguished two ways in which things can be brought about because of their likely effects. One way is through feedback from past cases; past outcomes, successes and failures, can affect what is done now. A number of different but analogous mechanisms can support this. I discussed two back then, Darwinian evolution and learning by trial and error—continuing to do things that have worked, avoiding those that have not. Another kind of learning, introduced just now in this chapter, can also have this role. This is learning by imitating others who are successful (and avoiding the imitation of failure). This has a mix of features of Darwinian evolution (as it is on the scale of a population) and ordinary individual learning. It’s a culture-sized version of trial and error in the individual.

All this is in the first broad category of ways in which things can happen because of their effects, the category involving feedback from past cases. The other category is the one where a future outcome is represented and sought, even if all this is new: I am doing X because I think it will lead to Y, though this has never happened before. It might be that X has never before been used to get to Y, though Y is familiar (perhaps X is a shortcut), or Y itself might be completely novel.

The distinction between plan and habit might be somewhat vague, and actions can have some of both. A bit of planning, some use of novel methods, might be laid on top of a habit that is more established. Habit-based behavior almost always has to include some fine-tuning for the circumstances, and this might be the beginning of the transition. At some point, though, we do see a new kind of choice. This is not found just in humans; rats engage in an imaginative “pre-play” of behaviors that involve navigation in space, using internal maps in their brains to try out possible paths. Eventually, we reach the situation where humans can consciously plan, using language to formulate what they want to do and how it might be done, and pursue goals that are arrived at through imagining, with little or no precedent in history at all.

Play that involves explicit pretense—I am the king!—arises early in young children. This starts as young as eighteen months (around the same time as those norm-enforcement behaviors I mentioned earlier in this chapter). It doesn’t seem completely unique to humans, though nonhuman cases, in a few other primates, seem rare.

My emphasis on the role of the imagined brings to mind a view developed in a bestselling book by Yuval Noah Harari. In Sapiens, Harari says that a key advance seen in human action, especially social action, is guidance by fictions. Fictions in his sense include religions, companies (like Peugeot), and money. I think that there is some role for fictions in such cases, but it is not the main thing going on. Many behaviors that Harari understands in terms of fictions are better understood with the idea of convention. In these cases, we have interlocking behaviors and expectations within a community that can be used to coordinate action that has large effects. Language itself is like this; it is a pattern of behavior sustained purely by convention, by people’s expectations that speaking and hearing will continue to align, more or less—align well enough to keep things going.

This is true of a lot of what Harari describes as fictions or myths. They don’t rest on something that is putatively real but actually not so (a fiction); they rest on convention-based patterns of behavior that have been reasonably stable, and that we, who are part of the pattern, have some reason to believe will continue.

A case Harari discusses that does sometimes look as if it involves fiction is money. Objects of no intrinsic usefulness—bits of paper, shells, records in computer files—become the focus of a huge fraction of our activities. In some cases, behaviors around currency might be guided by fictional beliefs about intrinsic value, but in general the practice is sustained by mutual expectations—the expectation that what I work for and receive (dollars, as indicated in bank accounts) will be seen as valuable by others. Often, expectations and actions that involve a government play a special role; tax payments are demanded in the form of dollars or euros. But this is not essential, and can’t always have been in play when early currencies arose.

The fiction view can seem exciting because it makes the whole enterprise, the edifice of coordinated human action, look precarious and fragile. And it is fragile. Conventions are inherently fragile. If we give up enough of the interlocking behaviors, it all falls apart. But human social actions in most cases are not held together by fictions. They are, in a way, more free-standing than that.

Writing and Time

These words—marks on a page, or images on a screen—bridge us. They bridge two people. So does spoken language, but writing is distinctive in its relationship to time. Written marks persist, bridging time as well as the differences between people. When you write just for yourself—notes, reminders, diaries—you are both sender and receiver, over a temporal gap.

The anthropologist Claude Lévi-Strauss, in his wry, moody memoir Tristes Tropiques (a book that begins, “I hate traveling and explorers”), discussed this aspect of writing: “Writing is a strange invention. One might suppose that its emergence could not fail to bring about profound changes in the conditions of human existence … It can be thought of as an artificial memory, the development of which ought to lead to a clearer awareness of the past, and hence to a greater ability to organize both the present and the future.” Perhaps literacy might be seen as a plausible marker of the transition from primitive life to civilization? But then: “Yet nothing we know about writing and the part it has played in man’s evolution justifies this view.” As Lévi-Strauss notes, most of the major transitions in human living occurred without and before writing, and the period after writing was invented included long periods of cultural stagnation. What writing is good for, he says, is controlling people: “the integration of large numbers of individuals into a political system, and their grading into castes or classes.” Tight social control is possible without writing, but writing firms it up.[1]

The outlines of Lévi-Strauss’s sketch correspond, at least roughly, to what is now believed about the origins of writing. Writing is thought to have appeared independently three or four times, first in Mesopotamia, perhaps around 3200 BCE, in Egypt soon after (probably independently), and later in China and Central America. Writing did not arise as an attempt to make permanent the transitory sounds of speech. Instead, its main initial roles were recordkeeping and administration. It was not a general-purpose system, but specialized for these roles. Many “graphic codes” are not based on the sounds of words at all, and the transition in a few cases to sound-based codes may have been prompted by the need to keep track of individual people—to write down proper names. Later, writing took on a wider range of roles. In Sumer (Mesopotamia), tablets with hymns, poems, myths, and allegories are seen from about 2600 BCE. (Does that seem a long wait, or a short one? To me it seems long—many hundreds of years.)

According to the French cognitive scientist Olivier Morin, the feature that Lévi-Strauss and I emphasized at the start of this section—the creation of a flexible, widely applicable new form of memory—might have been especially late to take hold. Outside of those narrow recordkeeping roles, the bridging achieved by writing was, in earlier stages, mostly an adjunct to other ways of carrying information forward.

Morin notes that in much of the ancient world, memorization was a highly prized skill. It was often an essential part of the curriculum in literate societies (in Mesopotamian, Jewish, and Hellenistic traditions). In ancient Greece and Rome, the “memory palace” or “method of loci” mental technology was widely taught and used. Here, a person memorizes a large collection of items by imagining a palace or other building (which might be real or made-up), and placing the items at particular locations within it. The items can then be encountered, “retrieved,” in those places later, on an imaginary path taken through the building. An older tradition of memorization used in Aboriginal Australian cultures combines the use of places, actual rather than imagined, with stories—a narrative is built that sets items to be remembered into a landscape, one that can then be physically traversed or mentally recalled. On a larger and more permanent scale, “songlines” or “singing tracks” tie songs to landscapes in a way that integrates navigation, ritual, and the maintenance of ecological knowledge.

Related to the primacy of mental memory even in literate ancient societies was a valuation of recitation—saying things out loud. In the formation of a treaty or alliance (Morin’s examples are from ancient Mesopotamia), spoken oaths were what mattered, even if a text served to help people remember. In other settings, shamans might use pictorial, writing-like codes to jog their memory during incantations. An inscription was an aid to speech, and only usable alongside other remembered knowledge. These uses of writing contrast with uses in which the aim is to get a message to someone at a different, perhaps distant time, someone to whom the information can be quite new. The transition to this modern role requires that texts become more self-contained. You need to know the language or code, but the text has to make sense without a lot of context and stage-setting that require memory or some other way of carrying information forward. Aboriginal Australian “message sticks” are an intriguing intermediate case. These carved sticks were used to send messages over long distances. The message was delivered orally by its bearer, and the artifact was, in its normal uses, an aid to recall and recitation (as in those Mesopotamian treaties). It also had a passport-like role. But at least in some cases, the meaning of a message could be read from the stick when the bearer was missing.

Morin and Lévi-Strauss emphasize the unobviousness of what seems obvious to us now—the boundless possibilities, in relation to time, that writing enables. But this broader use for writing did eventually take off, and writing become a general-purpose, long-term, highly precise memory for just about everything. External representations also lend themselves to manipulation and transformation. Mathematical symbolism, especially, is like this; knowing how to use a symbolism is knowing how to produce new formulas that take things further. A technology that started as a device for social control could also become central to the history of subversion and revolution—The Rights of Man (Thomas Paine, 1791), The Communist Manifesto (Marx and Engels, 1848). The internet continues the trend.

This side of writing—the time-bridging side, and to some extent the whole phenomenon—is a version or manifestation of something more general. This is a “looping” pattern. An action is done at one time to affect perception later. The shape of the activity doesn’t look much like a loop if you write something to be read immediately by another person. There’s a role for writing that is quite speech-like—achieving near-immediate contact, as with a phone text message. But writing also has that other role, where permanence matters, and if we zoom out our view a bit, a culture as a whole is continually laying down marks, meant to be read, that carry its way of living through time.

In cognitive science, when a person makes marks of some kind to read or make use of again later, this behavior is described as “offloading.” Information is offloaded from the brain to the wider world, and then taken up again. The practice is often more transformative than that term suggests. Through actions of this kind, an idea is not just externalized but also given a new form that can be worked with in different ways—the example of mathematical symbolism is again a good one. Drawing and painting can have the same role, along with other ancient ways of making marks, such as carving. All this is a combination of several kinds of action we’ve looked at in other chapters. Making a mark is a small piece of engineering, transformation of the environment (chapter 3). This is also a senderreceiver behavior (chapter 4), even if the receiver is the same person as the sender, at a later time.

Written language is not just a combination of sender-receiver interaction and engineering; it is a practice that embodies the power of each of these in a unique way. There are various practices of making marks to be seen, many pictorial traditions and “graphic codes.” In written language, speech itself, which has been shaped in social life to have great expressive power and flexibility, is carried over into the realm of inscription, where it can endure, and can be worked on in new ways.

Stepping back from writing, and looking at all the forms of action discussed in this chapter, a good part of the story of how we came to be us is the story of these patterns of action. We’re beings with a certain kind of evolved body and brain, but who we are is dependent to a particularly high degree on what we’ve done. It is a result of what we’ve built and continue to build, how we teach and imitate, which behaviors we encourage, and the ways we transform our surroundings. The twentieth-century biologist Richard Lewontin wrote a number of philosophically minded papers. One is called “The Organism as the Subject and Object of Evolution.” It claims that organisms are not passive recipients of evolutionary forces, but active in their own development and evolution. Lewontin meant this generally, and in his account of organisms as subjects he made use of many of the phenomena described in the first chapters of this book—niche construction, the chemical effects of life, and so on. This idea of an active role for all organisms in evolution is true to some extent, but it’s not a message that applies the same way all over. Humans have been active in our evolution to a particular degree, through culture and technology, and the loops discussed in this section are part of this. Our offloading, perception-feeding practices are part of our characteristic place in the world.

The Greek philosopher Socrates, back around 400 BCE, advised against a reliance on reading and writing, as he thought they led to shallow forms of understanding. People’s memories would dim. He imagined an Egyptian king addressing writing’s inventor: “You provide your students with the appearance of wisdom, not with its reality.”

At least, this is what we’re told about Socrates’s views by Plato, his student. Socrates did not write his philosophical ideas down. Plato did, and many he presented as the words of Socrates. Historians debate how much Plato’s Socrates has to do with Socrates himself. When there’s no written record, retellings serve the purposes of the tellers. Even when ideas are written, there’s still a good deal of this—people select, edit, and translate. But inscriptions can provide a very different degree of stability.

It’s possible to see anxieties about new technology as conservative and shortsighted. (The development of the printing press led some to concern about overload, as well as misinformation.) But neuroscience and psychology tell us that there are genuine questions here. “Cognitive technologies” change our minds as well as our social lives. Literacy, in particular, has significant effects on our brains. It increases the size of the corpus callosum, the main connector between our left and right hemispheres. This change is not genetic, but driven by individual experience. It also changes the way objects other than words—faces and houses—are processed visually, shifting literate people from a more holistic approach to one based on the tracking of specific features. A scanned literate brain looks different from one that’s not—an area of the brain lights up so reliably when literate people look at words that it’s known as the “visual word form area.” These changes don’t only occur when a person learns to read in childhood; if someone learns to read much later, the brain can be affected in these ways as well. The main concern of this kind today relates to the effects of smartphone technology, especially its effects on attention and memory, but the shifts in how our minds work started much earlier.

For each transition of this kind we can ask: Are we better off? We might make generalizations that contrast two ways of handling information. In one way, ideas are offloaded and marked down in an external, potentially public space. They are available to be worked on in new ways, and are potentially stable over long periods. In the other, retention is more psychologically active, relying on “onboard” memory and speech, and ideas are transformed differently.

In the case of music, traditions that use or reject inscription can flourish alongside each other without conflict. I marvel at notated music, at its stability and portability. The French composer Olivier Messiaen wrote “Quartet for the End of Time” in a German prisoner-of-war camp during World War II. Now it can be sent intact, note for note, to ensembles for new performances across the world. Musical traditions that rely on oral memory, with its more active re-creation, live on with their own greatness. (Music that relies closely on audio recordings is in some ways in between, but more akin to the unwritten traditions.) Some other parts of culture feature the same kind of coexistence, but in many contexts there seems to have been an ongoing choice, a series of forks in the road, between the two ways of handling information that I sketched above.

The next round of choices we encounter may have a different shape, though, if they involve internal cognitive aids, neurally implanted, whose use does not run through the channel of ordinary sensing and action. Might they move us toward restoration of some of an earlier cognitive style, strengthening our capacities for freewheeling internal manipulation? They would not take us all the way back if a strong role for text remains, and I don’t want this section to seem nostalgic for a Socratic, less literate way of being. I’m reminded of a quote from an interview with the Australian novelist Richard Flanagan, some of whose grandparents were illiterate and whose father was the only one in his family to value reading: “He never ceased to marvel till the end of his days that you can divine the universe with these 26 symbols. People who come from generations of literacy might have lost that sense of its transcendent and liberating power.”

Why Us?

It’s natural to ask one more question to finish this chapter. Why did animals of our kind go down this road, when and where we did?

This is more like two questions. Why was it animals like us (primates, mammals) rather than someone else, and how likely or inevitable was it that someone would do it? I’ll look at the first question here, and return to the other one later.

Biologists tend to emphasize contingency—the role of accident, the winding and easily deflected paths that took us to where we find ourselves now. Stephen Jay Gould imagined a “replaying of the tape” of evolution, from around the time of the Cambrian, and argued that we’d probably not get anything like the same sort of history a second time. Biologists looking just at the later stages have said similar things. Jared Diamond’s book The Third Chimpanzee casts us as an initially unremarkable species that did a remarkable thing. Others resist the message of contingency. Simon Conway Morris, a paleontologist who worked on some of the Cambrian fossils that led Gould to think in terms of accident, suspects that the general path we saw from back then is not surprising, and we might see something quite like it if the tape was wound back and the sequence began again.

People thinking about alternatives to the human evolutionary path often ask the question in terms of intelligence. Which other animals might have gotten very clever, or might do so if we leave the scene? My emphasis in this chapter has not been on intelligence as the human specialty, but on culture. If we imagine a species in which everyone is a lone genius, in an entirely non-cultural way, we are not imagining a species with anything like the role in the world played by humans. (Such a species would probably also be hard to evolve; the reflective, intense intelligence seen in humans might be something only likely to appear in a cultural species, even when that intelligence can be manifested in lone-genius form.)

The anthropologist Joseph Henrich, whose work I have used a lot in this chapter, has a story about the “Why us?” side of things. Primates (land-dwelling, warm-blooded mammals) evolved in the forests for arboreal life. This life gave them strong, grasping hands. They came down from the trees, in the story sketched at the start of this chapter, and these hands, especially after the primates began to stand somewhat upright, were freed for manipulation—for open-ended, exploratory manipulation of the objects around them.

I was reminded of this while watching the gorillas described at the start of this chapter. One male I watched for a while sat and—with those colossal, tree-trunk arms—fiddled patiently, intently, with some slender branches and stems.

As Henrich continues the story, once on the African savanna, these primates encountered many more predators, big cats and others. Imagine, for example, trying to sleep in such a setting. A general primate strategy in response to these kinds of threats is to form bigger groups. (In a variant of this story, Sterelny sees the formation of bigger groups after leaving the trees as a response to an opportunity—collaborative hunting—rather than a threat. It could be some of both.) In this enlarged social setting, the patterns of family life and child-rearing then changed, with longer childhoods, larger networks of relatives caring for infants, the formation of stable pairs, and other social shifts. With language on board at some stage, the rest is history.

Another biologist, Antone Martinho-Truswell, tells his own story about the evolutionary road to braininess and culture, and does so with an eye on a comparison between ourselves and birds.

Humans in many ways are atypical mammals, and this goes beyond obvious differences such as writing and making coffee. We are also different in our long lifespans and reproductive habits, including the way we look after children. Humans are fairly monogamous, at least compared to other mammals, and our children are helpless when young. These features are unusual in mammals, but similar to what is seen in many birds, especially parrots. With his eye on those similarities, Martinho-Truswell identifies an unusual evolutionary path that birds went down first, and that we discovered, in a modified form, later.

In Martinho-Truswell’s story, the birds’ version of this path begins with their unusual longevity, which was enabled by flight (very useful for escaping predators). A number of features stem from this, but Martinho-Truswell emphasizes especially some traits surrounding reproduction and the raising of young. Biologists distinguish between precocial and altricial offspring. Precocial offspring become independent quickly—they can move around and feed themselves soon after hatching or birth. Altricial offspring are helpless and need a lot of care. Most birds are altricial. Birds also tend toward monogamy, or at least a situation where both parents are involved in the raising of the young. I say they “tend toward” monogamy; there are plenty of exceptions, and even when a species appears monogamous, often the females engage in a lot of matings outside the relationship. The term “socially monogamous” is sometimes used in these cases, and that arrangement seems very common in passerine birds (the big group that includes more than half of all bird species). Parrots, who are next door to passerines on the tree, appear in many cases to be more genuinely monogamous, and parrots often show intense pair-bonding.

For Martinho-Truswell, long lives and close family ties lead to an intensely communicative intelligence in parrots and some other birds. This package of features also tends to be self-reinforcing—smartness, sociality, long childhood, and so on. Put it all together, and you get an evolutionary “rocket,” a path to a life of extremes.

Martinho-Truswell thinks we did something similar, tens of millions of years later. In our case, some initial braininess got the process rolling. This also made us long-lived, and the same package of traits surrounding reproduction and child care could then take hold. We ended up, as parrots did, with a highly social and communicative form of intelligence, and culture and technology followed.

In Martinho-Truswell’s story, our highly social way of living is “downstream” of those characteristics involving child care and reproduction. For Henrich, the move toward more social living is “upstream” of those characteristics; as we encountered the problems of life out of the forest, we became more social and developed new patterns of family life.

Animals can end up very social and brainy despite living differently from both humans and birds. Dolphins are large-brained animals, and full of human-like quirks such as mirror self-recognition and play. They are not helpless when they are young (I guess that would be very difficult in the sea), and also not at all monogamous, with no care of young by fathers. They are very social and communicative, though. Sociality itself seems to drive the story of their high intelligence.

Given all this, could dolphins have taken off in a human-like way, and achieved a technologically complex, dominating role on Earth of the kind that we have? Might they still do so if we leave the scene? Dolphins do have glimmers of culture. Once we ask about technology, manipulation becomes an issue, though. Like fish, dolphins have bodies built for swimming and can’t do a lot of manipulation of objects. This is also harder in the sea than on land, as we saw in chapter 3. They might become more amphibious in a takeover scenario, but they’d need some bodily changes. Dolphins as they are now do show some tool use; they appear in the rather short lists of tool-using marine animals. They use sponges to protect their noses when probing for food in the seafloor. While working on this chapter I learned that some dolphins wear long strands or clumps of grass draped over their dorsal fins, apparently to attract attention from other dolphins in social settings. But all this is limited, and they are highly social animals without being invested in technology, tools, or niche construction. When one imagines their possible futures, it would take them a long way off their current path to get them into a more human-like life in those respects.

In a comedic but often insightful series of books (The Hitchhiker’s Guide to the Galaxy), Douglas Adams imagines that dolphins are actually the smartest animals on Earth, but prefer to live as they do, with none of the fuss and clutter of human life. If that was all true, the fact that they are better off living as they do now would not stop dolphins from going down an evolutionary path toward a more technological way of living if there was some advantage to those who took the first steps, then an advantage to those who took the next step, and so on. The relevant kind of advantage here involves survival and reproduction, in comparison to other individuals in the same species. Humans may have been happier as hunter-gatherers than in early farming societies, but if they were, that would not have been enough to stop them from being outcompeted by people living in larger, settled groups. In the dolphin case, it’s not easy to see an evolutionary road toward technology and a state-based life in any case. Our primate ancestors on the savanna had grasping hands and lived in an environment where niche construction and technology came readily, with the aid of the stable, handier materials of dry land. This led humans not just to an evolutionary rocket (to use Martinho-Truswell’s term), but eventually to literal rockets as well.

While we are in the sea, what about octopuses? They have great manipulative ability, also a willingness to engage with novel objects, and some species put much effort into the construction and tending of dens. But with respect to the kind of path we are talking about here, they face other obstacles. Again, it is not just a matter of being clever; it is a matter of becoming cultural.

Some animals are well set up for culture, even if they are not there now, and some are not. Octopuses are not. They are not very social, engage in no parental care at all once their eggs are hatched, and have very short lives. The high-density octopus sites that I discussed in chapter 3, Octopolis and Octlantis, seem quite special. There’s no teaching of children and no other cultural transmission in the wild (as far as we know). A bit earlier in this chapter, I talked about the evolution of new systems of memory—imitation, apprenticeship, writing things down. These are all ways of accumulating knowledge and skills. Octopuses have trouble with these sorts of things on nearly every scale or, more accurately, little interest in them.

In his book Built by Animals, which was helpful to me back in chapter 3, the biologist Mike Hansell imagines a conversation between a Martian space traveler and a Venusian time traveler who meet in a hyperspace bar several million years before the present. The time traveler, who has returned from a trip into the future, surprises the space traveler, who has been spending some time visiting Earth, by saying that in a few million years some of Earth’s animal life would have complex technology, including the beginning of space travel. He adds that it will be primates who achieve it.

The Martian who has just returned from Earth says: “What, from that lot? You’re kidding me … I have had a stick waved at me once or twice and I’ve heard they can shape stones a bit but I would have put my money on the birds.”

Yes, for a long time, birds were far more elaborate builders and engineers. I am not sure about the Martian’s bet, though. We should be mindful of the costs of the miracle of terrestrial flight—the difficulty of having a body and limbs that can manage that, and the limitations in other areas that result. Earlier in this chapter, I described the impressive nests of weaverbirds. Hansell says at one point that these might be just about the summit, not only in fact but in principle, for avian engineering. Contrast all this with our primate-style life—grounded, grasping, grubbing around at the roots of things.

In Greek myths and later reflection on them, especially in writers like Nietzsche, a distinction between the Apollonian and Dionysian is sometimes seen as a big divide. The division is named after the Greek god of light, sun, music and dance (Apollo), and the god of wine, vegetation and fruit, intoxication and ritual madness (Dionysus). The procession of socially complicated animals in the years after the asteroid-caused extinction strikes me the same way, with birds as Apollonian, creatures of the air and music, and primates as Dionysian denizens of vegetation, pushed into big and integrated groups, and thence into culture, by the perils of life out of the trees.