“What Ostrom found empirically is that there exists a certain community size below which people act as collectivists, protecting the commons, as if the entire unit became rational. Such a commons cannot be too large. It is like a club. Groups behave differently at a different scale. This explains why the municipal is different from the national. It also explains how tribes operate: you are part of a specific group that is larger than the narrow you, but narrower than humanity in general. Critically, people share some things but not others within a specified group. And there is a protocol for dealing with the outside.”