These two factors, which tend to define educational requirements from an occupational standpoint, obviously explain some of the increase in mass schooling, but just as clearly they do not explain all of it.  A complete picture of the functions and functioning of education in the United States and other capitalist countries would require a thorough historical study of the manner in which the present standards came into being, and how they were related, at each step of their formation, to the social forces of the society at large.  But even a sketch of the recent period suffices to show that many causes, most of them bearing no direct relationship to the educational requirements of the job structure, have been at work (302-303).