The City of the Future: A Conversation with Antoine Picon and Carlo Ratti

This interview is part of The Rules We Live By, a series devoted to asking what it means to be a human living by an ever-evolving set of rules.  The series is made up of conversations with those who dictate, think deeply about, and seek to bend or break the rules we live by.

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TO UNDERSTAND THE city of the future, look no further than the evolution of digital urban maps. Dynamic, ubiquitous, and varied, they have become inseparable from the cities they represent, and are a vital and growing part of a city’s infrastructure.

This insight is at the center of Atlas of the Senseable City (2023), a collaboration between professors of history and architecture Antoine Picon and Carlo Ratti. Richly illustrated with maps from MIT’s Senseable City Lab, Atlas of the Senseable City places the modern city in historical context. No longer defined by its physical imprint, today’s city is vastly enlarged through its digital twin—and to fully access it means opening a digital map.

This profound transformation not only changes how we understand cities, but also how we build them. As architects, Picon and Ratti explain why “smart” has ceded its place to “senseable,” how to design for hybrid physical-digital spaces, and, perhaps most important, what it means to have hope for the city of the future.

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JULIEN CROCKETT: In Atlas of the Senseable City, you trace the evolution of urban maps, culminating in the digital maps that we see today. Before we get to the cities that they represent and how maps help us imagine their futures, how do you define a map?

ANTOINE PICON: For centuries, maps were understood to be representations of cities, but it was always more complicated. Traditionally, there have been two schools of thought, a contrast represented by Leon Battista Alberti, a Renaissance scholar, and Leonardo da Vinci. Alberti conceived of maps as databases registering significant places in a city, whereas Da Vinci understood the map to be a representative image, a bird’s-eye view of the city. So, what is a map? Well, it’s both a database and an image.

CARLO RATTI: Database, image, and also … hallucination! Maps also serve as projections of ourselves. Think about the situationists and their psychogeographic maps of Paris, portraying one’s subjective experience of a space.

And the modern digital map adds another dimension to our understanding, right? In your book, you discuss the blurring of the distinction between the digital map and the physical environment: “Whereas traditional urban maps were perceived as abstractions from the city’s everyday physical existence, the cartographic documents discussed here appear to be inseparable from it, as if digital cities were now inseparable from their physical twins.” Taking it further, you describe the map as having evolved to a point that it has now become a part of a city’s infrastructure. What do you mean?

AP: This largely relates to geolocation. As the Silicon Valley guru Mark Weiser observed, technology that succeeds disappears. I’m struck by how geolocation has created such a profound revolution and in succeeding has become almost invisible. Behind the merging of maps and infrastructure is the fact that you can now associate places with digital content. There are a number of consequences from this intimate link, such as the ability to track things that are moving. Maps used to be frozen in time and took time to put together. Now, they include near real-time information, which also raises the issue of mapping and monitoring.

Infrastructure is also generally something we take for granted. It is often the most invisible technology because it supports what we do every day. You remember that the metro exists once there is a strike, which happens often here in Paris. You take electricity for granted until, there again, it doesn’t work. Now, we take for granted that, wherever we go, we can localize something and know where we are. And many systems take for granted that you can follow in real time where things are going. This is what I mean by the map as infrastructure. It has become a support that enables a lot of things that we do.

The framework of map as infrastructure really expands the possibilities of what a map is and what it can cover. I was struck, though, by your references in the book to Jorge Luis Borges’s “On Exactitude in Science” and Lewis Carroll’s Sylvie and Bruno Concluded, where you write that perhaps maps today have attained the size of cities and, like the maps in Borges’s or Carroll’s texts, “they coincide almost point for point with the ground they cover.” Is that true?

AP: Yes and no. Yes, because pretty much every region of the world is covered in some form now. Nothing escapes being mapped, monitored. But, no, because no map is an exact representation. A map is not reality. Bringing it back to the texts, Carroll is a bit more ambiguous, but Borges actually suggests that the ambition of the map was to cover the empire, not necessarily to be the empire. In other words, we cannot escape the fact that a map is always partial. It always filters. Which is why, by the end of the book, we’re really saying beware, because maps are produced, and they have bias. Bruno Latour in Paris: Invisible City (2006) writes that the more you see, the more partial is the picture, a visual equivalent of the uncertainty principle. What is new today, though, is the capacity of coverage, which is without equivalent in the past. And by “map” today, we have to understand that it’s no longer just a sheet of paper on your desk. It’s actually a series of infrastructures, including satellites, computers, tablets, databases, etc.

If we understand the purpose of architecture and design to be building a world for humans, is there something fundamentally different about building in digital spaces versus physical spaces?

CR: As we spend more time immersed in digital flows, we are becoming hybrid in nature. Yet, I would say that there is something fundamentally different to physical space—“inevitability.” Digital space can lead to what we could call a “homophily trap.” The digital realm allows us to algorithmically filter and curate experience, isolating us within ideological echo chambers. This exacerbates political and social polarization, as we’re less likely to encounter perspectives that challenge our own. Conversely, physical space allows people of diverse backgrounds to come together, interact, and experience a shared humanity. We need the inevitability of physical space more than ever in the digital era.

AP: Picking up on our hybrid nature, I wrote a book called The Materiality of Architecture (2021) in which I argue that the digital cannot cover the complete array of sensations that we have in the physical world. Very often, we are in hybrid physical-digital spaces, but there are things unique to physical space, beginning with the fact that we’re born and we die in physical space. What is complicated is that we now need to design for people who spend one-third of their day on a screen. At the same time, they have bodies and experience sensations uniquely linked to the physical world. So, in some ways, designing spaces for humans has become more complicated than before.

To your point about how designing for humans has become more complicated, is it because the definition of “being human” has changed?

AP: We have become different because of digital technology. But it’s linked to something more profound. The “digital” is not only a technology; it’s also culture. You don’t understand digital technology if you try to compare it to the steam engine or electricity. It’s more comparable to the printing press. It changes our social relations. It changes the very nature of who we are, both individually and in groups. Take the crises of fake news, urban rumors, or the strangeness of US politics (it’s not only the US, by the way). These are all partially linked to the fact that we’ve become different, and that living together has become more complicated all of a sudden. We are very destabilized and redefined by the digital condition. The task of the architect is to make spaces in which people feel comfortable, but also spaces in which we relate to each other. And in societies that are so divided, it makes the job of the architect more daunting than in the past.

You also write about the evolution in how we perceive cities—from collections of physical objects to circulation and flow to now billions of elementary occurrences recorded digitally. What does this evolution mean for city planning?

AP: It means something complicated. When we were just dealing with physical things, a Renaissance “urban planner” (or the equivalent) would focus on objects and public spaces. Cities of circulation and flows introduced a complication because, in addition to physical bodies, you have to consider the water running in pipes, the sewage running under the street, and, later, electricity and all its accompanying infrastructure. Now we have all those things plus the pixelation of events and occurrences. We have to move at more levels. It’s like a physicist who must work both at the level of quantum mechanics and classical Newtonian mechanics. You have to be more agile in terms of thinking about the nature of the city.

But our perception of the city has also been dramatically enriched. We are now able to understand and monitor things, and with artificial intelligence, we’re going to understand much more. Where I probably differ from Carlo is that I’m not as much of a techno-optimist. I’m not quite a techno-pessimist either, but rather than solving problems, I think technology displaces them. So, in some ways, we know far more about cities, but also the challenges for cities have increased.

CR: Neither am I a techno-optimist! Rather, I believe technology’s exogenous force is causing us to rethink how we do things. Ancient Romans had two words for city: “urbs,” the physical environment, and “civitas,” the community of citizens. For the first time, technology allows us to visualize and understand civitas: how people move in space, how they connect, and also how they segregate into what Richard Sennett and I call “liminal ghettoes.” Architects and urban planners can now take into account the civitas rather than just the urbs.

I think both your optimism and pessimism come through in the book, particularly in your hopes for the city of the future.

AP: I’d still say I’m an optimist because I believe optimism is not a state of mind; rather, it’s a moral attitude. Given the overall state of the world, one has to remain optimistic because that’s what we should do. Ultimately, the problem with the digital is political. What will we do with it? It’s very unfortunate that the digital has been mobilized over the past few years to propagate false truths and statements, and new mythologies. The digital could be a formidable tool to explain things and help people participate. Wikipedia, for example, is still a fabulous thing, provided that you double-check the information now and then. It’s without equivalent in the past. A city is now like that. We have formidable new capacities, but it’s up to us to use them in a positive way.

CR: I agree with Antoine. If we were to borrow Karl Popper’s words, we could say that “optimism is a duty.” It is a duty because optimism deals with the future, and the future is not predetermined but will depend on what we do.

Turning more specifically to Atlas of the Senseable City and the MIT Senseable City Lab, can you explain why you decided to use the term “senseable” rather than, for example, “smart”?

CR: When we started the lab at MIT, around 10 years ago, the buzzword was “smart city.” But I did not like it, as it implies a city optimized like a machine, focusing heavily on efficiency and technology-driven solutions. It overlooks the city’s key ingredient: people, with all their complexities. We came up with the term “senseable” to signify a more human-centric approach. “Senseable” suggests a city that is able to sense but is also sensible—not just smart in a technological sense but also responsive to the needs, behaviors, and emotions of its inhabitants. The name of the lab then inspired the collection of our maps.

AP: And these visualizations were pathbreaking, resetting the clock in terms of the types of questions we can ask about cities.

What is it about maps that make them such a powerful form for studying and conveying information?

AP: Maps are one of the ways in which we make sense of the world, and their history has been closely associated with modernity. You can write a history of the city from the Renaissance onwards through maps. So, maps are a way of making sense of the city. Further, in our digital world, where everything is represented through zeros and ones, even what you find concretely in databases doesn’t make sense empirically unless you’re a specialist. But as soon as the information becomes dots on a map, we believe we’ve understood what it is. So, maps are one of the privileged ways we make sense of the world. But this is tricky. We tend to believe maps, but maps are always biased and processed in certain ways and not others.

CR: Yes, and maps are even more important in the age of Big Data and AI. Unlike AI, our brains cannot make sense of gigabytes of data. However, they can understand them when they become maps. Paradoxically, that is where AI fails, and our human brains have the upper hand.

Atlas of the Senseable City is organized around four dimensions of cities—motion, connection, circulation, and experience. Why did you decide to organize the book in this way?

AP: There are two polarities in these dimensions. Connection and experience are really about how we make sense of cities both individually (experience) and collectively (connection). Motion and circulation are about what can be observed. So together, they are about registering motion, movement, and events, and then how we experience them. In so doing, we can learn about the possibilities for socialization and for building more collective environments.

Starting with the first dimension, motion, one of the projects in this section that I found fascinating was the Wanderlust project. Can you tell us how you organized the project and what you learned about human mobility?

CR: It all started when I was a student at Cambridge University at the turn of the millennium. It was then that I realized that the path I followed between my bedroom at Darwin College and my department on Chaucer Road was, in fact, two different paths. On the way to Chaucer, I would take one set of turns. On the way back home, another. Surely one route was more efficient than the other, but I had drifted into adapting two, one for each direction. I was consistently inconsistent, a small but frustrating realization for a student devoting his life to rational thinking. Was it just me or were my fellow classmates—and my fellow humans—doing the same?

Years later, at the Senseable City Lab, we found the tools to answer my question. By analyzing anonymized digital traces from cell phones, we were able to study human mobility on a large scale. Then it became clear that I was not the only one who navigated this way. Humans are not optimal navigators; rather, we deviate from the shortest possible path consistently. What we do is minimize angular deviation—or, in technical terms, vector-based navigation.

Why? Evolution is a story of trade-offs, not optimizations, and the cognitive load of calculating a perfect path rather than relying on the simpler pointing method might not be worth a few saved minutes. After all, early humans had to preserve brain power for dodging stampeding elephants, just like people today might need to focus on avoiding aggressive SUVs. This imperfect system has been good enough for untold generations.

However, people are no longer walking, or even thinking, alone. We are increasingly wedded to digital technologies, as we were saying before. This experiment reminds us of the catch: technological prostheses do not think like their creators. Computers are perfectly rational. They do exactly what code tells them to do. Brains, on the other hand, achieve a “bounded rationality” of “good enoughs” and necessary compromises. As these two distinct entities become increasingly entangled and collide—on Google Maps, on Facebook, or in a self-driving car—it’s important to remember how they are different from each other.

Staying with human universals for a moment, I want to move to the second dimension, connection, and discuss COVID-19. You documented and illustrated the result of the stay-at-home orders through the MIT Email Collaboration project, which revealed that, while the internet allows us to maintain ties with close friends, physical spaces are needed to form casual acquaintances. Can you describe how you conducted this study and what you hope we learn from it?

CR: This study was conducted at the MIT campus, where we analyzed anonymized data on email communications between students, professors, and administrators. We built a communication network that compared interactions both before and after the campus COVID-19 shutdown. This actually happened somewhat by accident—we set up the experiment to monitor email communications before knowing that we’d soon be given the lockdown order. Suddenly, we had the perfect natural experiment: comparing the ways our ties are affected by proximity.

While strong ties—those with close friends and colleagues—remained robust or even strengthened, our weak ties suffered. Weak ties—connections that are not part of our inner circle of friends—are crucial for introducing us to new ideas, challenging our preconceptions, and broadening our understanding of the world beyond our immediate social circles. The weakening of these ties in the absence of physical interaction underscores the importance of physical spaces in forming and maintaining a diverse human network.

Did COVID create new trends? Or did it simply accelerate trends already in place?

AP: Crises like COVID do accelerate trends. Take the example of the horse plague of the 1870s in North America, which incapacitated something like a third of the horses. One of its consequences was to accelerate the mechanization of transportation, a process that had already begun. COVID has clearly accelerated moving a number of activities online. I was surprised by how seamlessly we were able to transition to Zoom. But to go back to what I said about architecture, I think COVID also reminded us of our bodies. When you begin to constantly measure the number of feet that separates you from your neighbor, you realize that the digital is not everything. It also revealed how dependent we are on human relation. People have become a bit weird. (Very often, I tell myself that I’ve probably become weird too; it’s not only others.)

Perhaps most importantly though, COVID has also caused us to take a closer look at the question of our relationship with the nonhuman world. You know, a couple of bats near Wuhan probably shattered the foundation of the human world. I think our book in some ways is pre-COVID. If I had to write it today, I would make the connection between the digital and the natural world more present.

Can you say more about how you might update the book?

AP: Carlo will expand, but I think there has clearly been an inflection in the Senseable Lab’s work toward increasingly considering nature both at the micro and the macro level, from the world of bacteria to the world of trees. But a book is always a moment in what is a continuous movement, at least until the author dies. It’s a moment of reflection.

The funny thing with crisis is that it’s a little bit like war, where you forget certain things so quickly, but it’s also so difficult to forget other things. As a historian, I’ve thought a lot about those questions. I think COVID was forgotten extremely quickly and, at the same time, there are a number of things we’re stuck with. For example, I think it has completely changed interbody relations. There is still hidden somewhere a degree of apprehension when we’re too numerous in a room.

CR: As the resolution of data has increased over the years, new phenomena can be studied. This includes, for instance, unveiling the world of microbes inhabiting our sewage network, as in projects such as Underworlds. Or the classification of greenery in cities around the world with Treepedia. Somehow, the digital can help us better understand the natural—and our relationship to it.

Another area I want to focus on with COVID is the diagnostic implications of maps, which relates to the third city dimension, circulation. In your book, you write about the connection between maps and the field of epidemiology. Can you briefly tell us about that relationship?

AP: In the 19th century, there was a cholera outburst that repeatedly struck cities in Europe. At that time, we were discovering all of the problems of big cities, like poverty and disease. At the same time, there was a gradual development of the idea that maps might be a way to diagnose problems, which is today even more present because maps are connected to modeling; this can allow us to not only diagnose but also try to steer cities. That capability started to emerge in the 19th century, and it really took off through the connection between maps and statistics.

The modern instantiation of the diagnostic map can be found with the Underworlds project—can you describe it?

CR: The inspiration for Underworlds was John Snow’s 1854 map of London, which mapped cholera cases and water wells and helped explain the transmission mechanism of the disease. Underworlds imagines a future in which sewage is mined for real-time information—insights on eating habits, genetic tendencies, drug consumption, contagious diseases, and overall health. Medicine has revealed that we are superorganisms—for every cell in our body, there are around 10 bugs living and interacting with us. Underworlds aims to explore that through sewage and to understand something that you could call our “collective gut.”

Interestingly, Underworlds led to one of the largest wastewater-monitoring plans in the United States during COVID-19.

Moving on to the last city dimension, experience, you write that it’s the most fundamental dimension for understanding how maps and the “social imaginary” are intimately related. What do you mean by that?

AP: To live in a society is of course to be part of a group, but it’s also to share collective representations, beliefs, and values, which are not completely objective. There is a famous book by historian and anthropologist Benedict Anderson titled Imagined Communities: Reflections on the Origin and Spread of Nationalism (1983), which argues that a nation is actually partially an imaginary community. Take France, for example. It’s comprised of a lot of extremely different people, but what holds them together are a number of collective representations of values and beliefs. The United States is also made of many different groups held together by a number of common imaginations, for better or for worse, many of which have become clichés. We all have these kind of cliché images, but clichés are part of our imagination. Maps are interesting things because they are powerful tools to both build clichés and disrupt them.

How do maps capture these immaterial essences?

CR: The inputs are always “collective representations,” as mentioned by Antoine. But AI can help us collect them and analyze them on an unprecedented scale.

AP: Using a French example, in the 19th century, there was a map of public instruction produced based on whether newlyweds and their witnesses signed the official wedding record using a cross or their name, with use of a cross signifying that the signer didn’t know how to write. From this rose the map of public instruction in France, which divides the country into two zones: the Northeast, which is educated, and the Southwest, which is less educated. From this map rose the Sainte Geneviève Line, which has had an extraordinary posterity and came to be a common representation of the French elite in the Northeast. But more recently, the Northeast, which was industrialized, became the French Rust Belt, and the Southwest, because it had the advantage of being near the Mediterranean Sea, thrived. Brittany, for example, which was dirt-poor and supposedly one of the most illiterate regions in France, benefited from its geography and became a place where many people want to live. The consequence of this has been that, over time, the line has become completely inverted, in no small part because of the map and what it came to represent. In the US, maps of red and blue states, of poverty and crime, also help build a society’s imagination. Maps build an image on which we project our own experiences, which can be extremely powerful.

I want to end with the city of the future and how maps can help us imagine possible futures. I was a bit surprised when I read under the description of the Favelas 4D project that the city of the future likely looks a lot like Rio de Janeiro’s favelas. Can you explain why you believe that?

CR: The Favelas 4D project suggests that the city of the future may resemble Rio de Janeiro’s favelas in its complexity and adaptability. This does not imply underdevelopment but rather highlights the efficiency and resilience found in informal settlements. These areas, often overlooked, exhibit a unique blend of social organization, resourcefulness, and adaptability—qualities essential for future urban development. We can study them in new ways—researchers on our team are carrying 3D scanners through the narrow alleys and down the sloping hills, hoping to capture every inch of the 1.5-square-kilometer neighborhood (around 300,000 data points are generated every second). In doing so, we can learn valuable lessons in creating more flexible, responsive, and sustainable urban environments.

Our decisions in this generation—to ignore, eradicate, or integrate—will help decide the destinies of unborn billions in the years to come. Favela residents are already experts in managing informality—some were mapping their communities with pen and paper long before we began our work with 3D scanners. Working alongside them, we can find a new balance between the top-down and bottom-up forces that shape cities.

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Antoine Picon, an architect and historian, is the G. Ware Travelstead Professor of the History of Architecture and Technology at Harvard University Graduate School of Design.

Carlo Ratti, a practicing architect, is professor of urban technologies and director of the Senseable City Lab at the Massachusetts Institute of Technology, and professor of urban planning at the Politecnico di Milano.