One generalized truism is that European cities are walkable and transit-supportive, and North American cities are not. This is not universally true, but it's often thought to be directionally true. However, a recent paper called "Car Dependency in Urban Accessibility" reveals that this may not be as true as we think.

The study introduces something called a Car Dependency Index (or CDI). What it effectively does is compare accessibility to jobs and services within a city by car versus public transit. They did this for 18 European and North American cities, and here's what they found:

A positive score (red on the map) means that a car can access more opportunities than public transportation, and a negative score (blue on the map) means the opposite. What's not surprising is how car-dependent the outskirts of most cities are, including European cities. Car dependency was high in over 70% of the urban territories that they analyzed.

What is more surprising to me is that most cities don't have much, if any, blue. The best-case scenario seems to be a lot of white (which represents accessibility parity between cars and public transit). Hmm. Does Manhattan really not have any blue? The glaring exception is Paris and, to a lesser extent, Zurich, though keep in mind these are only city proper boundaries.

Another finding is that car dependency remains a primary driver of car ownership, even when accounting for income. What this means is that if you took two people with the exact same income, one living in transit-rich Paris and the other living in the suburbs of Rome, the person in Rome is much more likely to own a car.

Once again, this supports the obvious fact that if we design cities so that they're inconvenient to navigate without a car, well, then more people will get cars. It's not easy to build a transit network that can compete. Individual lines won't do it. The key word is "network." And you need the right land-use policies to support it.

Cover photo by Alessio Ferretti on Unsplash

Charts from "Car Dependency in Urban Accessibility."

Movable chairs have been a feature of Parisian parks since the 18th century. Chairs are more comfortable than benches, and movable ones allow you to direct yourself toward the sun, cluster in groups, or just situate yourself so that you can prop your legs up and read a book.

Now, here's a brief story of how this came to be.

At the outset of this innovation, park chairs weren't free. If you wanted a bench upgrade, you had to pay. Private concessionaires would rent them out to visitors (like umbrellas at a beach), maintain them, and presumably ensure that things were kept generally tidy around the grounds.

Then, around 1923, the iconic green Sénat chair was designed by the Ateliers de la Ville de Paris. If you've ever been to Paris, you know this chair (see cover photo). It comes in only three models: chair, armchair, and recliner, all of which are green. RAL 6013 green, to be exact.

Eventually, the Sénat chair was imposed as the Parisian park chair. By 1955, it was the only possible option that could be rented out by concessionaires in places like the Jardin du Luxembourg. This set the stage for it to become one of the most recognizable symbols of the city.

But due to the popularity of these chairs and the fact that people would rather not have to pay to sit in a park, it was decided in 1974 that the chairs should be free, and they were bought from the concessionaires.

In 2002, Frédéric Sofia designed an offshoot of the chair called the "Luxembourg." The Luxembourg is made of aluminum, as opposed to steel, and is therefore lighter. It's also available for sale to the general public, whereas the Sénat chair is exclusively for city parks.

The result of this centuries-long tradition is an iconic symbol for the city and an established culture of employing movable chairs in public spaces. A humble movable chair may not seem like a big deal, but in the world of public spaces, it is.

Try to incorporate movable chairs into a park or public space today and, invariably, someone will tell you that it can't or shouldn't be done. They will say the chairs will be stolen, vandalized, and/or weaponized by hooligans. Perhaps not.

Today, there are some 4,500 movable chairs in the Jardin du Luxembourg alone. Paris shows us that it can be done.

Cover photo by Brigi Harkányi on Unsplash

Here are some interesting charts from a16z showing that, despite its dominance today, tech still represents a smaller percentage of the US stock market than railroads did at the turn of the 20th century. One parallel you could draw from this is that "tech" as we know it today, may not be so dominant a hundred years from now.

But railroads continue to play a critical function in the modern economy. They are still the most cost-effective way to move heavy goods over long distances. A single freight train can carry the load of several hundred semi-trucks.

The more interesting parallel might be the one that a16z raises in its post: railroads both led to further economic growth and rewired the way businesses and organizations were structured.

Railroads were a new kind of business requiring massive scale and coordination, which led to new ways of thinking about "management." Perhaps not surprisingly, it was around this time (1881) that the world's first collegiate business school was formed at the University of Pennsylvania.

The parallel to AI today, as argued by Jack Dorsey and maybe others, is that it's going to similarly rewire how businesses are organized and what middle management does:

"Instead of absorb and route information, maintain alignment, pre-compute decisions, etc.—the kind of coordination that management typically is responsible for—in an AI business, humans move to the edges, to focus their judgment on customer contact and human interactions."

At least, this is the hypothesis.

But if it does prove to be true, let's consider what we often discuss on this blog, which is: what will it mean for our cities and built environment? Well, what I find interesting about the above quote is that it suggests AI will push humans further toward the things that we are uniquely suited to do: interacting with other humans and building meaningful relationships.

And if that is, in fact, what happens, then there's no more efficient place to be than in dense urban cities. Looking someone in the eyes, shaking their hand, and slurping ramen noodles together at a busy bar counter is not something that AI will be able to do for us.

Cover photo by Mike Beaumont on Unsplash

Charts from a16z