Introduction: From Babylon to Boston, cities have always been hubs of economic growth and cultural activity. Cities bring people from all over the world together to live, explore new ideas, and interact in new ways. The form of cities is often influenced by technological change - whether it is the discovery of new resources (ancient Babylon developed early trade routes and ports) or the acquisition of new energy (the Industrial Revolution gave rise to countless factories in Boston) - the history of cities is the history of technological innovation.

As our world becomes increasingly digital, cities are beginning to change. But the next generation of cities won’t be built of wood, bricks, or steel. This time, they’ll be built of code.

Before we delve into the digital city, it’s best to take a step back and think about where the unique magic of cities comes from.

The essence of a city is a multitude of complex systems - these systems integrate various parts and interact with each other so that the entire system can operate in a coordinated and coherent manner.

Let's take a simple example - a car. You can't make a car just by putting parts together. To turn parts into a car, you have to place the parts in a specific way and let the parts interact with each other so that the whole machine can operate as a whole. The premise of the existence of a "car" includes not only many parts, but also the synergy between the parts. The function of a car also goes beyond the many parts on the car (the car can drive). This is called emergence.

The impact of emergence is profound. We humans owe our existence to emergence—from the organs in our bodies to the cars we drive—these are emergent properties exhibited by complex systems, each of which is made up of simple parts that interact with each other. This is also true of cities.

Technological innovation will encourage more people to flock to cities. As more people flock in, division of labor will begin to emerge, and people will become interdependent. This will further promote the growth of cities and form a network of people, culture, and resources that are interconnected and interdependent. After this interconnected network emerges, cities will also show properties that are completely different from the individual parts that make up the city.

That's the magic of the city.

Cities in the digital age

To understand the future of digital cities, we must first understand the composition of digital cities. In physical cities, people, land, and institutions are important elements. In digital cities, identity, digital space, and protocols are important.

While identities and protocols are already being explored by several web3 projects, Metropolis is focused on exploring digital spaces in depth, which is what makes up the majority of the modern internet. Digital spaces are places where people gather, chat, build, and collaborate. From GeoCities to MySpace to Reddit communities, everything is a digital space.

Over the past decade, highly connected digital spaces have created unprecedented opportunities for individuals to communicate and interact. These spaces allow us to digitally express our identities, explore our passions, and even make a living.

In this way, digital spaces are the precursors to digital cities—where people connect and form new relationships that make emergence possible. However, the thriving economies or interconnected subcultures that digital cities might spawn are not yet in place.

This is because the construction of digital space suffers from an original sin: materialization on borrowed territory.

"Realizing on borrowed turf" means that these spaces are based on platforms that do not belong to the people who live there. For example, the digital spaces on Discord are reified on borrowed turf because these spaces belong to Discord. Discord has full power to change the API or restrict access to some data, or even shut down the server without any explanation.

While this compromise may seem acceptable on an individual level, the complexity of the digital spaces built on these platforms (and the potential for emergence) is limited by the connectivity and relationships that can occur within these platforms. For example, Discord servers cannot connect to Twitter Circles, and Twitter Circles have difficulty connecting to Reddit communities. Without interoperability between platforms, the complexity of their digital spaces (and the potential for emergence) can only be limited to what can be built within the platforms themselves.

Before we go any further, it is important to understand that Web2 platforms have no incentive to make their digital spaces interoperable. Not only does it require standardizing data across platforms, it also undermines the most popular business models. With the walls built by network effects and revenue models that rely on the ability of a specific platform to capture attention, there is no reason for platforms to care about interoperability.

A quick note: “Borrowed territory” in the above context simply means that the people who inhabit the digital space currently constructed by the Internet do not own the corresponding infrastructure. This concept is different from stolen territory, which refers to many illegal acquisitions of land in history (inseparable from colonialism and imperialism). If we want to distinguish between these two concepts in detail, I am afraid we need to write a separate article.

Web2 platforms always try to trap users and communities in their own digital space, while Web3 introduces a completely new paradigm.

Web3 is not materialized on borrowed territory, but provides the possibility for all spaces to be materialized on a shared ledger (blockchain). This means that the space does not belong to the platform, but to the people who create and participate in it. In essence, Web3 gives sovereignty to digital space.

This paradigm shift means that digital spaces are interoperable, and therefore, digital spaces can become highly interconnected and interdependent. As the interconnectivity and interdependence between these spaces increase, the complexity of these systems also increases.

Digital cities emerged.

DAOs represent a gradual shift towards sovereign digital spaces. Tools such as multi-signatures give DAOs the ability to materialize their own sovereign spaces, where the owners are the people who participate.

So why isn’t there a highly interoperable, interdependent DAO network yet?

Although sovereignty is a prerequisite for emergence, it is not enough to turn scattered digital spaces into digital cities. If we want DAO to become a digital city, we need to consider what characteristics are required for emergence to occur in a complex system.

1) Relational Order Complex systems are made up of many different parts that are scattered around, without a centralized authority, but are connected to each other at a local level. New layers are created, creating hierarchies between systems. In this way, order emerges from the local relationships between the parts, not from a centralized authority.

2) Interdependence Complex systems are highly interdependent, and their parts are interdependent. Interdependence is often a product of specialization, where elements of a single system are all good at one thing and help other elements become more efficient. In this way, the system can benefit from economies of scale.

3) Interconnectedness Complex systems are also highly interconnected, but this is not the same as interdependence. As the parts of a system become highly connected, they become more and more like a network. This phenomenon is similar to the theory of the Ship of Theseus, in which even if every part of the ship is replaced, the ship is still the same ship.

4) Adaptability Adaptation and autonomy do not occur from a centralized authority, coordinating all parts, but rather occur locally, with each part being able to respond to changes in the local environment according to its own logic and rules. This is how ant colonies adapt to changing environments, even if each ant has no idea of ​​the overall response.

These properties all have one thing in common: they define how the parts of the system relate and interact, which makes emergence possible. Such relationships are important not only within a DAO, but also between DAOs.

The concretization of digital space on the chain gives us sovereignty, but if we want to turn digital space into a digital city, we also need a high-fidelity framework to reproduce the complex network of relationships within the digital space.

Metropolis builds relationships and connectivity into the protocol. Our pods encapsulate multi-signature functionality, allowing organizations to maintain their own sovereignty while defining complex relationships within and between pods. This infrastructure enables DAOs to become highly connected, interdependent digital cities.

As DAOs continue to evolve, we will also see the latest forms of city embodiment. FWB, Cabin, etc. have begun to guide their organizations through the perspective of the city, towards the future of local Internet.

But these cities do not exist in isolation. Physical cities are limited by geography, physics, and borders, but digital cities have no real limits. In digital space, the cost of transactions and information exchange is not affected by the physical laws of the physical world. As a result, digital cities have great potential, and their degree of interconnection and interoperability will be unimaginable in physical cities.

The DAO space is often compared to an ecosystem. But we think of it more like a city of cities — a metropolis of interconnected, interdependent organizations. Like a city, this metropolis is not only rich in its striking architecture or colorful residents, but thrives on the network of people, cultures, and economies that live together.