Knowing and liking may be strongly correlated within groups of established friends, but that tells us nothing about how people in general react to learning more about others.

Whenever we decide we don’t like someone—that neighbor with the dog, for instance—we start to avoid them and so gather less information about them. But when we strike up a friendship with someone, we spend more time with them and learn more about them.

We see communication on a personal level the same way we see it on a societal level: as a reliable way to form and strengthen bonds.

why social media’s effects have been so different from what we expected—why the technology of connection has produced more strife than harmony. Now that we’re all virtual neighbors, we’re all in one another’s business all the time.

So the casual contacts that promote empathy and fondness never happen. Enmity, once provoked, becomes self-reinforcing.

Neighbors become enemies, the condo researchers discovered, for a very different reason: “environmental spoiling.” The closer you live to another person, the more exposed you are to his habits and opinions.

because his proximity guarantees his irritating habits and opinions remain always in view, your resentment, and your antipathy, will fester.

proximity seemed to breed animosity more often than it did affection.

The reason neighbors often become friends, previous research had shown, is simple: they run into each other a lot.