General Historic Observations.--Prolificity is a much discussed
subject, for besides its medical and general interest it is of
importance in social as well as in political economy. Superfluous
population was a question that came to consciousness early; Aristotle
spoke of legislation to prevent the increase of population and the
physical and mental deterioration of the race,--he believed in a
population fixed as regards numbers,--and later Lycurgus transformed
these precepts into a terrible law. Strabonius reports that the
inhabitants of Cathea brought their infants at the age of two months
before a magistrate for inspection. The strong and promising were
preserved and the weak destroyed. The founders of the Roman Empire
followed a similar usage. With great indignation Seneca, Ovid, and
Juvenal reproved this barbarity of the Romans. With the domination of
Christianity this custom gradually diminished, and Constantine stopped
it altogether, ordering succor to the people too poor to rear their own
children. The old Celts were so jealous of their vigor that they placed
their babes on a shield in the river, and regarded those that the waves
respected as legitimate and worthy to become members of their clans. In
many of the Oriental countries, where the population is often very
excessive and poverty great, the girl babies of the lower classes were
destroyed. At one time the crocodiles, held sacred in the Nile, were
given the surplus infants. By destroying the females the breeding
necessarily diminished, and the number of the weaker and dependent
classes became less. In other countries persons having children beyond
their ability to support were privileged to sell them to citizens, who
contracted to raise them on condition that they became their slaves.

General Law, and the Influence of War.--In the increase of the world's
population, although circumstances may for the time alter it, a general
average of prolificity has, in the long run, been maintained. In the
history of every nation artificial circumstances, such as fashion, war,
poverty, etc., at some period have temporarily lowered the average of
prolificity; but a further search finds another period, under opposite
circumstances, which will more than compensate for it. The effect of a
long-continued war or wars on generation and prolificity has never been
given proper consideration. In such times marriages become much less
frequent; the husbands are separated from thei