The division of life into age-groups was prominently adhered to in antiquity, though there was considerable disagreement as to their precise identification. The Pythagorean philosophers (see pythagoras) identified four (Diod. Sic. 10. 9. 5), whereas Hippocratic writers (see hippocrates (2)) acknowledged seven ages of man, each seven years in length (Poll. 2. 4). Since adult society was primarily organized on a two-generational principle, a threefold division probably served most practical purposes, viz. παῖς, νέος, and γέρων in Greek, puer, iuvenis, and senex in Latin. Mental ability was judged to be strictly a function of ageing, as indicated by the fact that there were minimum age qualifications for administrative and executive posts. So an Athenian councillor had to be 30 years old, as, probably, did a Spartan ephor (see also age classes). Similarly the Roman cursus honorum or ladder of office prescribed minimum ages for all magistracies. Belief in the magical power inherent in certain numbers, notably seven and three, meant that certain ages were believed fraught with danger. Augustus is said to have expressed considerable relief ‘at having survived my climacteric, the sixty-third year’ (Gell. NA 15. 7. 3). Censorinus' De die natali (On Birthdays) provides an invaluable compilation of information about age terminology, etc.
There is little evidence with which to estimate the age structure of the population of ancient Rome, and even less that of ancient Greece because Greek funerary monuments, unlike Roman ones, rarely record age at death except in the case of extreme youth and extreme longevity. What follows must therefore be treated with extreme caution, as must any such model. There were relatively few elderly people in the sense in which we understand the word ‘elderly’, and a much larger proportion of adolescents and young. It is estimated that in Rome ‘more than a quarter of all live-born Roman babies died within their first year of life’ (Hopkins). About one-third of the children who survived infancy were dead by the age of 10. Upper-class females in their early teens tended to marry males who were at least ten years older. In Rome, however, the legal age for marriage was 12 and 14 for females and males respectively (see marriage law). Sepulchral inscriptions, no doubt biased in favour of the upper classes, suggest that in the Roman world the median age of death was 34 years for wives and 46.5 for husbands. The study of skeletal remains from Classical Athens has produced comparable results, viz. 35 for women and 44 for men. Life expectancy was appreciably lower for women at all social levels, largely because of the debilitating and often lethal effects of childbirth. Probably less than one per cent of the population attained the age of 80 and anyone who did so was judged remarkable, as [Lucian's] catalogue of octogenarians in Macrobii suggests. Notwithstanding the brevity of human life, threescore years and ten still constituted the proper quota of years (cf. Solon 27. 17 f. West, IE2). Maximum life-span, viz. about 100 years, appears to have been the same in antiquity as it is today. Old age is commonly described as hateful and detestable in classical literature (though cf. Cic. De senectute) and many lives would have been characterized by increasing incapacitation and loss of mobility from the beginning of the third decade onwards. (The study of skeletal remains at the Romano-British cemetery at Cirencester indicates that 80 per cent of the population suffered from osteoarthrosis). Particularly disadvantaged and scorned were spinsters and widows. Certain races had a reputation for extreme longevity, notably the long-lived Ethiopians, whose life-span was put at 120 years. Many Greeks and Romans would only have had an approximate notion of their exact age in years, as the expression P(lus) M(inus) ‘more or less’, which is frequently found on Roman tombstones, indicates. See menopause; population.