|Tallini World||Ancient Greek world
society or polity
|Ancient Roman world
society or polity
|Observer||Oikos [οἶκος] (household)||Stirps (Cognomen-based)||Household or family||4.5||2.5|
|Sixth World||Genos [γένος] (made up of a number of oikoi [οἶκοι])||Gens (Nomen gentile- or Gentilicium-based)||Hamlet or clan||45||25|
|Fifth World||Phratry [Φρατρία] (made up of 2 or more genē [γένη])||Curia (made up of 10 gentes)||Parish or nation||450||250|
|Fourth World||Phyle [φυλή] (made up of 3 or more phratries [φρατρίες])||Tribus (made up of 10 curiae)||Village or state||4,500||2,500|
|Third World||Ancient Athens (made up originally of 4 phyles [φυλές] based on blood ties; Cleisthenes reforms redistributed the Athenian population into 10 phyles based on the area in which one lived)||Roma (antiqua) (made up of 3-35 tribus or 14 regiones Romae antiquae)||Town or country||45,000||25,000|
|Second World||Ancient Greece||Italia antiqua (insulis exceptis) (made up of 11 regiones Italiae Augustanae, which excluded Sicily and Sardinia)||City or region||450,000||250,000|
|First World||Ancient Greece + Magna Graecia + Asia Minor + other colonies (Archaic period)||Imperium Romanum||Conurbation or quasi-world||4,500,000||2,500,000|
The average Roman family had five or six kids, but only two or three of them lived to grow up . So the average Roman family had four to five members, 4.5 on average, excluding slaves. The average American household in 2015 consisted of 2.54 people .
By the end of the Republican era, a name for an aristocratic male citizen comprised three parts (tria nomina): praenomen (given name), nomen (or nomen gentile or simply gentilicium, being the name of the gens or clan) and cognomen (name of a family line within the gens). Sometimes a second or third cognomen, called agnomen, was added. The nomen, and later, cognomen were virtually always hereditary. The praenomen was often abbreviated in writings.
Females were officially known by the feminine form of their father's nomen gentile, followed by the genitive case of their father's (husband's if married) cognomen, and an indication of order among sisters. A woman usually did not have the praenomen or agnomen, unless the parents chose to give her those.
Pretty sound research now shows that the entire population of the Roman Empire was somewhere around 4 million to 5 million people by the end of the first century BC .
Advanced political science thinking: it takes a real country, or town, to raise almost any child, and it may take nothing less than a city, or region, if he or she is gay or lesbian
http://cesidio.org/It_takes_a_country.pdf (PDF document in letter format)
http://cesidio.org/It_takes_a_country-a4.pdf (PDF document in A4 format)