ABSTRACT
In the modern city, the patterns of social classes, ethnic and religious groups, and inequality are spread out physically in the form of relatively homogeneous neighborhoods. The residents of the latter drive into the city in the morning, use its services all day, and then creep out at night, taking with them much of the city's income and wealth. The absence of replacements for the new emigres from the city means that some of the first rungs in the nation's traditional ladder of upward mobility have been eliminated. The city historically has harbored the greatest inequalities, the largest numbers of those who have most and those who have least. That is what the city has become—a sandbox. A sandbox is a place where adults park their children in order to converse, play, or work with a minimum of interference. The adults, having found a distraction for the children, can get on with the serious things of life.
