High-engagement obsessives are another key to this. In a community where it's nobody's actual job to spread knowledge and values of the community, the highest-volume interactors – the most engaged – become standard-bearers of the community. Since they are often more obsessive and dedicated yet visible, this raises the stakes of the community to greater obsessiveness and dedication.

In online scenarios, the result is that many can say, well, I am dedicated to X, but I'm not as extremely dedicated as Y... where Y may be literally one of the most X-dedicated people in the entire world.

When you have this majority illusion, some high-engagement obsessives, and throw in some producers of writings (news, documents, popular literature and orientation literature such as FAQs), you have an engine for converting dedication into social goods such as a sense of belonging, friendship, and most of all, self-identification.

The ability to create and sustain these communities in many forms, for any topic, worldwide, is the miracle of the internet.