Years ago, I lived in a 5th floor Manhattan walk-up. For two years, I shared the stairwells and some walls, the sounds of our music and the smells of our cooking, with about fifty people I never spoke to beyond a casual hello or a shrugging complaint about the landlord. It wasn’t an exceptionally unfriendly building, it was just how we needed to live in order to maintain some privacy in such close quarters. It was a building, not a neighborhood.