Standard text-books have usually presented a cut-and-dried account of three stages of Roman education: primary from age seven, with the grammaticus from age twelve, and rhetoric from about fifteen or sixteen. Most detail is devoted to the rhetorical stage, as that is where the future leaders (politicians, lawyers, army generals) were trained; so there is much detail on rhetorical exercises, declamation, and the like. Such accounts present the Romans as formalistic and rigid, and the focus on adolescent upper-class males tells us nothing about the socialisation and training of younger children, of girls, the lower classes and slaves. (Slaves comprised at least a quarter of the population of a large city like Rome in the late Republic and High Empire, which had a total population of about one and a quarter million at its height, in the 2nd century of this era.)