In a perceptive article, "It's a Wonderful Block," about the little stretch of New Haven, Connecticut, that he calls home, Mark Oppenheimer ponders why successful neighborhoods "work." Engaging in a combination of microhistory and social psychology, he found merit in the diverse mix of people, of different ages, backgrounds, and viewpoints, knit together by the physical structure of overhanging trees and generous sidewalks and a commensurate, shared spirit. As Oppenheimer concludes, neighborhoods have a recognizable "feel," although one that is "both fragile and contingent."

Too often we imagine the digital realm as ethereal, otherworldly. But it's human beings all the way down. Humans are the true endpoints of the network, humans are the ones that have structured that network and written the software to do—or not do—certain things. As the social history of technology has shown, we can't discuss digital communities without discussing non-digital, distinctly human emotions. Any sound theory of community building must be built upon feelings from human encounters, online or off. And when we talk about human feelings, seemingly small actions, attitudes, and structures can have an outsized impact.

Technical and physical platforms can promote, or hide, certain kinds of behaviors and thus shape a community in positive or negative ways. Twitter, for instance, doesn't rub it in your face when someone unfollows you. That's not a random (non)feature; it was a decision that a human made at some point about the social cues of the platform, and many of these little elements of Twitter stand in distinction from the sidelong-glance social log that is Facebook.

Similarly, the structure of most scholarly society meetings provide other social cues for their communities. The raised podium, along with fairly few opportunities for in-person commentary, perhaps pushes scholars toward actions that would seem, in most contexts, not very neighborly. However, other parts of these meetings, like the cocktail hours, have more friendly, unifying agendas.

As Oppenheimer notes, successful communities have a higher prevalence of "sidewalk life," of frequent casual encounters, rather than a "backyard life" of independent existence with rarer and more formal encounters with one's neighbors. For those who want to build a community, enhancing the former through social and technical structures seems like a good place to start. The significance of apparently trifling tweets might be deeper than critics imagine.

At the same time, we should remember that it's all fragile and contingent, requiring constant tending by all members of the community.