Economists have a term for assets that can be exchanged one-for-one without loss of value: fungible. One dollar is convertible. A barrel of West Texas Intermediate crude is fungible.
…A group of people bound together by years of shared reference, inside jokes, and collective memory is not like that.
And yet we continue to treat communities as they are.
When a platform migrates its user base to a new architecture, the implicit promise is that the community will survive the move. When a city demolishes public housing blocks and offers residents vouchers for market-rate apartments across the city, the implicit promise is that they will rebuild with what they had.
These promises are always broken, and the people making them either don’t understand why, or they are too blind to see it to trust the rest of us.
What did Robert Moses do wrong?
Robert Moses displaced an estimated 250,000 people during his career, razing entire neighborhoods to make way for expressways and public works projects. Moses’ defense, then and now, is utilitarian: more people benefited from the infrastructure than were harmed by its construction. The calculus assumed that displaced residents could form equivalent communities elsewhere, and that relationships broken by a highway cutting through a block could be replaced with relationships formed in a new location. Jane Jacobs spent much of her career arguing that this was extremely wrong. The old neighborhood was not a collection of people who lived near each other; It was a living organism that had its own immune system and its own way of metabolic transformation. When Moses bulldozed over it, he killed a community and scattered the remains.
Jacobs understood that the value of a community does not lie in the people as separate units. The value lies in the specific, unobtainable web of relationships between them. You could move every single resident of one street to the same new street in the same new suburb and you would not get the same community, because community is a function of ten thousand microscopic transactions of time and reciprocity that no one can track and no one can order.
…and what economists forget
In one model, agents are interchangeable. Consumer A and Consumer B have different preference curves, yes, but they react to similar incentive structures in predictable ways. Community is what you get when agents stop exchanging for each other. When Alice needs a need, not a “neighbor” He The neighbor, the one who was watching her kids at the time, the one who knows she is allergic to peanuts. Relationship is specific, and specificity is the enemy of variability.
This is why so many attempts to “build a community” from the beginning end up producing something that looks like a community but works like a mailing list. Startup that launches a Discord server and calls it a community // Coworking space that holds a monthly mixer and calls it a community, etc. What they have actually created is a directory of loosely associated strangers who share a single contextual overlap.
This is the initial condition for community, but it is not community itself, and the difference is like the difference between a pile of wood and a house. Raw materials are necessary but extremely inadequate.
When platforms go away, communities don’t move
The Internet has run this experiment dozens of times by now, and the results are consistent. When a platform dies or goes defunct, its community doesn’t simply move to the next platform, it disintegrates, and those who arrive in the new space find that the social dynamics are different, the norms have changed, and a large number of the people who made the old space feel like home are gone. The Russian acquisition of LiveJournal scattered its English-speaking community to DreamWidth and eventually Twitter. Each successor captured a fraction of the original user base and none of them captured the culture. The community that existed on LiveJournal in 2006 has become extinct and cannot be reassembled. The specific circumstances that created it, a particular moment in Internet history when blogging was new and social media had not yet been colonized by algorithmic feeds and engagement optimization, no longer exist.
You can see the patterns in the death of Vine and the migration to Snapchat x TikTok, the decline of Twitter and the splintering of Threads, Bluesky and Mastodon. In every case, the platform’s architects//successors recognized that the product was the platform and the community was an emergent feature that would re-emerge under similar circumstances. Their relationship was completely the opposite. The community was the product and the platform was the container, and when the container breaks, the product spills and evaporates, and some of it is lost forever.
Dunbar’s Layers + Archeology of Trust
Robin Dunbar’s research on social group size tells us that humans maintain relationships at several levels: approximately five intimate relationships, fifteen close relationships, fifty good friends, and one hundred and fifty meaningful acquaintances. These are not arbitrary numbers; They reflect cognitive and emotional bandwidth constraints that are probably neurological in origin. What Dunbar’s model tells us about community has been underappreciated. If a community is a network of overlapping Dunbar layers, each member of the community has a unique experience, shaped by where they sit on the web. There is no “community” in any objective sense. There are as many communities as there are members, each a different cross-section of the same social graph, and this means that when you lose members, you lose entire subjective communities that literally did not exist anywhere else.
When a Roman city was abandoned, the physical structures were destroyed at varying rates. Stone walls lasted for centuries while cloth faded over the years. When a community disintegrates, its social structure is similarly destroyed. Institutionalized relationships, stone walls, may survive: people will still know each other’s names and professional roles. With active effort, close friendships can last for some time. But the trust of the environment, the willingness to lend a tool without asking or the willingness to tolerate a small irritation because you have built up enough goodwill to absorb it, that is the fabric, and it comes first. Once it’s gone, what’s left = a structure that looks like a community but has lost the ability to function like a community.
Why doesn’t “create new” work?
A fantasy popular among technologists and policy makers is that community can be engineered. If you identify the right variables and implement the right interventions, you can build communities on demand. This fantasy has a name in urban literature: it is called “new town syndrome”, after the observation that Britain’s post-war new towns, carefully designed with all the amenities needed for a community, produced widespread disunity and social isolation in their early decades. Stevenage had shops, schools, parks and pubs. What he did not have was history. Residents had no shared past nor gradually accumulated social capital. There was proximity without context, and proximity without context is crowding.
The same problem arises in every domain where one tries to instantiate a community from a blueprint. Corporate culture initiatives and neighborhood revitalization programs optimize for visible markers of community, events, and shared spaces, while ignoring the invisible substrate that makes those markers meaningful. It’s like building an elaborate birdhouse and assuming that the birds will come, and when they don’t, birdhouse makers usually conclude that they need a better birdhouse, rather than questioning how the birdhouse gets you in.
You can’t replay history
The destruction of a community is largely irreversible. You can rebuild a building and you can replant a forest and, given enough decades, get something that resembles the original ecosystem. But a community that took twenty years to develop its particular structure of norms and mutual knowledge cannot be developed again in twenty years, because the conditions that shaped it no longer exist. People have grown older, the context has changed, and the specific convergence of circumstances that brought those particular individuals together in that particular configuration at that particular time has ended. Communities are path-dependent in the strongest possible sense: their current state is a function of their entire history, and you can’t replay history.
Ursula K. Le Guin wrote Deprived About the tension between a society that values radical freedom and the structures that have emerged organically to make collective life possible. His protagonist, Shevek, discovers that even in a society designed to prevent the accumulation of power, informal hierarchies and social obligations develop on their own, taking shape based on nothing more than time and proximity. Le Guin understood that community structure is not designed, it is deposited, like sediment, by the slow accumulation of interactions that no one planned and which no one controlled.
So what do we actually owe existing communities?
If communities are irreplaceable, if they cannot be replaced once they are destroyed, then every decision that disrupts an existing community has a cost that is systematically underestimated. The cost doesn’t show up in a spreadsheet because it’s not a line item, it’s the loss of a particular, specific, immutable social configuration that offers its members things that can’t be bought on the open market: ambient trust and the comfort of being known.
Displacement – whether physical or digital – is costlier than anyone’s budget. The burden of proof should fall on the displaced, not the displaced, to demonstrate that the benefits of disruption outweigh the destruction of social capital that took years or decades to accumulate. And glowing promises of “we’ll build something even better” should be treated with the same skepticism as a contractor who promises to replace your load-bearing wall with something decorative. Frankly, this is nonsense.
Communities are not the resources to be adapted and they are not the user base to be migrated. They are the accumulated remains of people repeatedly choosing to remain in relationship with each other under specific circumstances that will never happen the same way again.
It is foolish to consider them convertible, and we are too willing to let this happen unchallenged.
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