A great many cities are experiencing difficulties which are nothing new in the history of cities, except in their scale. Some cities have lost their original purpose and have not found new one. And any large or rich city is __1__ going to attract poor immigrants, who flood in, filling with hopes of __2__ prosperity which are then often disappointing. There are backward towns on the edge of Bombay or Brasilia, just as though there were on the edge of __3__ seventeenth-century London or early nineteenth-century Paris. This is new is __4__ the scale. Descriptions written by eighteenth-century travelers of the poor of Mexico City, and the enormous contrasts that was to be found there, are very __5__ dissimilar to descriptions of Mexico City today—the poor can still be numbered __6__ in millions. The whole monstrous growth rests on economic prosperity, but behind it lies __7__ two myths. the myth of the city as a promised land, that attracts immigrants __8__ from rural poverty and brings it flooding into city centers, and the myth of the __9__ country as a Garden of Eden, which, a few generations late, sends them flood __10__ -ing out again to the suburbs.