In the late 1980s, Alex—we’ll refer to ourselves as Alex and Mike—worked at the Middleton Twentieth Century Theater in Madison, Wisconsin. This was a 1940s’ corrugated-iron Quonset hut that was built in less than a week. Tickets were 99¢ for all seats, all shows, all times, and all ages. The movies shown were six months old and the ones almost no one still wanted to see. There was one screen, a monophonic speaker above it, and the skeleton of a rat in the basement that the manager would show to new employees.
Alex worked both the ticket booth and concession counter, and his initial responsibility was to take a dollar bill from the customer, and jam a penny and the sweaty ticket stub into the customer’s hand. Alex would then step back out of the booth and into the lobby to sell soda, popcorn, and Mike and Ikes to the same customer(s). In the summer, he would drag out the Toro lawnmower from a closet beneath the projection booth and go outside and mow the strip of grass behind the gravel parking lot. The manager would walk out to watch as Alex sweated in a white shirt and tie, inside a cloud of brown grass bits and flying pebbles.
Change was slow to come to the Middleton. The manager showed Alex how to take inventory, which meant counting the dusty Hershey Good & Plenty boxes in the display case and subtracting the number from yesterday’s total to get the sales for the day—usually a box or two. Alex earned $3.60 an hour—a couple cents more than the minimum wage at the time. The theater’s air-conditioning had broken down in the early 1980s and still needed to be fixed. One night, the manager said that if no one showed up for the 9:25 show, Alex could close up early. Two people showed up, unfortunately, and bought popcorn. At the end of the film, Alex put the gross sales for the day of just over $11 in a lockable canvas bag and transported it to the outside drop box at one of the downtown banks.
Despite being only a generation ago, this scene is unrecognizable now. Most children in the United States watch movies on a device, and cash is used in only about 10 percent of US transactions. Alex’s work experience—like repairing film with a splicing device or informing customers, individually, of showing times when they phoned in—would not count for much on a modern résumé.
Thinking of movies makes us think of ratings, which were around back then, but nothing like we have now. You can now find ratings of everything imaginable—hotels, restaurants, roads, dating services, and even massage parlors. Customers are incredibly picky compared to the Middleton Theater customers, who would watch anything. Think of the modern customer’s one-star motel review on TripAdvisor, complete with a half-dozen pictures of a paint chip on a dresser drawer. It makes you want to ask, “What did you expect for $39?” Compare that customer to two customers on the hot sidewalk outside the Middleton Theater in August 1990, when the manager was trying to talk them out of the movie because he had just finished sealing a pack of fifty $1 bills and they had a twenty. The manager first tried telling the couple that the movie had started ten minutes ago and that the beginning was crucial. When the couple said they didn’t mind—“Two tickets, please”—the manager tried, “It’s really hot in there” and told them to wait while he went to check. He returned ten minutes later with a thermometer/humidity meter saying, “It’s really hot in there: 85 degrees with over 90 percent humidity!” Finally, the man said, “The hell with this!” and he and his girlfriend left (the next customer, who came shortly after that, paid with a dollar bill and went straight in).
We all think we know why this 1980s’ scene seems so long ago. From e-mail in the 1990s, to iPhones and Facebook in the 2000s, to a proliferation of ephemeral social media, rapid change has become part of our expectation, not just in generational gaps, but in intragenerational ones as well. Some people expect to see a time when brains are wired directly into the Internet. If that comes to pass, it certainly will be different to be human. But this book is not about what it might be like to have a chip in your brain or transhumanism more generally. In fact, this book is not about you as an individual at all. Rather, it’s about your culture. More to the point, it’s about those scores or hundreds of generations of people of past centuries in your cultural ancestry who passed on and contributed to the habits and knowledge that seem so normal to you now. This book is also about how that system of cultural inheritance is radically changing. It’s about how the scene at the Middleton Theater represents a process of culture that, invisibly, differs far more than simply in terms of gadgetry.
In his 1976 book The Selfish Gene—long before he became a prolific and cranky Twitter user—Richard Dawkins coined the term meme for an idea, style, or behavior that spreads from person to person within a culture. In the mid-1990s, philosopher Daniel Dennett described a meme’s-eye view that modeled ideas as viruses whose survival depends on their spreading among their human hosts. Applying Dawkins’s criteria, memes spread through longevity, fidelity, and fecundity. In other words, successful memes are retained in the memory, and then get copied accurately and often. The Internet is the perfect medium for memes, and people talk regularly about them, especially in relation to online text, tweets, pictures, and so on, which are copied and shared. A picture of Michael Jordan crying has become so widespread that young people today might know him better by this meme than by his basketball career.
This book is not about how to spread your memes. If you want that, just read a marketing blog such as knowyourmeme.com. This book is about how culture evolves, and frankly, how culture evolution was never only about spreading memes. Evolution is about three things and three things only: variation, transmission, and sorting. Everything we discuss in this book boils down to these three components of the process that has shaped humans into the large-brained, hairless apes we are today. That’s the genetic part of human evolution, but it’s the cultural part that has shaped and continues to shape what humans everywhere do and say.
Thinking of the new world in terms of memes and your individual experience on a smartphone is fun, but it doesn’t really get us anywhere. We are going to ask you to think a bit harder about things. We’re going to draw on quite a few different sciences, from anthropology to archaeology, economics, evolutionary biology, and even (briefly) physics. Most important, we will ask you to think on a different scale than you might be used to—one that includes many, many people, over many generations, sharing and tweaking different units of culture.
Humans have evolved to learn cultural know-how and teach it to the next generation, with occasional small adjustments that can track environmental change. The knowledge embedded in culture has instructed people in how to address environmental challenges, feed themselves and their group, and efficiently store that knowledge as cultural practice, which makes it learnable and heritable. Humans became cultural animals through individual characteristics such as large brains and long life spans, but also through group-level features such as kinship networks and specialization of knowledge.
These features, however, often stand in stark contrast to those that define us today. Fewer people now inherit their occupations; technological change has become so rapid that previous generations of knowledge are seen as irrelevant; we are no longer learning from the wisest individuals in the group; and the new, online world is filled with masquerading “experts,” both human and nonhuman. How do we plan for this world? How will knowledge accumulate if learning occurs through different pathways than it has for the past hundred thousand years? How will knowledge be sorted? Through a survey of some of the main technologies that are reconfiguring the way we learn, this book explores the implications for the future of cultural evolution.
Our central premise is that the shape of cultural transmission has changed dramatically over recent decades, from one that is thin and deep to one that is shallow and broad. Thin and deep—what we can call “traditional”—is the shape of local learning of knowledge that is inherited through ancestors and changes slowly, on the time scale of many generations. Traditional knowledge is finely tuned to the local environment over many generations of slow cultural adaptation. Broad and shallow—shaped like a “horizon”—describes recent knowledge, or just information, that is shared widely, including potentially internationally. In the horizon regime, the tempo of knowledge creation has accelerated to the point of little connection with ancestral knowledge.
This metaphor, from thin and deep to shallow and broad, underlies this book and divides it into two parts. The first five chapters are about traditional aspects of cultural evolution. The transition occurs in chapter 6, where we look at how certain long-term traditions, such as marriage and diet, are rapidly changing through shallow and broad horizons. Our shallow and broad discussion continues in the next few chapters through the science of networks, prediction markets, and the explosion of digital information. Finally, in chapter 10, we ask whether artificial intelligence may solve this overload problem by learning to integrate concepts over the vast idea space of digitally stored information through time. Although we are not going to wax poetically about a “singularity,” it could be unprecedented in the hundreds of thousands of years of human culture.
We take this opportunity to thank Bob Prior, executive editor of the MIT Press, for his unflagging support of the project. We also thank John Maeda, editor of the Simplicity: Design, Technology, Business, Life series, published by the MIT Press, for graciously accepting our book into his series. This is the second book we have published with Bob and John—the other being I’ll Have What She’s Having: Mapping Social Behavior (2011). Finally, we thank Gloria O’Brien and the MIT Press’s Deborah Cantor-Adams for providing excellent editorial suggestions.