In this we see first of all the fact that the requirements of literacy and familiarity with the numbers system have become generalized throughout the society.  The ability to read, write, and perform simple arithmetical operations is demanded by the urban environment, not just in jobs but also for consumption, for conformity to the rules of society and obedience to the law.  Reading and figuring are, apart from all their other meanings, the elementary attributes of a manageable population, which could no more be sold, cajoled, and controlled without them than can symbols be handled by a computer if they lack the elementary characteristics of identity and position.  Beyond this need for basic literacy there is also the function of the schools in providing an attempted socialization to city life, which now replaces the socialization through farm, family, community, and church which once took place in a predominantly rural setting.  Thus the average length of schooling is generally higher for urban populations, and the shift of population from farm to city brings with it, almost as an automatic function, an increase in the term of education (302).