Since the beginnings of civilization, cities have been crucibles of progress both for societies and individuals. A great city, wrote Rene Descartes in the seventeenth century, represented “an inventory of the possible,” a place where people could create their own futures and lift up their families.
What characterized great cities such as Amsterdam—and, later, places such as London, New York , Chicago, and Tokyo—was the size of their property-owning middle class. This was a class whose roots, for the most part, lay in the peasantry or artisan class, and later among industrial workers. Their ascension into the ranks of the bourgeoisie, petit or haute, epitomized the opportunities for social advancement created uniquely by cities.