In my London neighborhood, I frequently stopped by friends’ houses if I was walking past, and ended up, quite often, staying for a cup of tea or a drink. It didn’t surprise me if someone stopped by, either. It was neighborly, and relaxed. But we’re now living in a way that assumes no one will casually visit, so of course no one does.I think it was Christopher Alexander and his colleagues, who wrote the amazing A Pattern Language, who explained the importance of casual, unplanned meetings in creating a sense of community. This is why, they said, people have such fond memories of their days at university or in the army. We have that kind of interaction still, here in Great Barrington, on Main Street on weekdays (not on weekends–there are too many tourists and local people stay away). in our neighborhood, when the weather’s good, we wave and sometimes stop to talk when people are outside. But I wouldn’t dream of simply dropping in, and I’d be surprised if a neighbor turned up unannounced on my doorstep.