tribe of nomad Bedouins;
and we have seen that infant life is held sacred by these peoples.
Marriage is regarded as a duty, and childlessness as a misfortune or a
disgrace. The forward look, characteristic of the Hebrews from the
first, made every Jew desirous to leave descendants who might witness
happier times, and one of whom might even be the promised Deliverer of
his people. No Hebrew of either sex was allowed to be a servant of vice;
abnormal practices, though screened by Canaanite religion, were far less
common than in Greece or Italy. To this wholesome morality Christianity
added the doctrines of the value, in the sight of God, of every human
life, and of the sanctity of the body as the 'temple of God.' To the
Pagans, the continence of the Christians was, next to their affection
for each other, their most remarkable characteristic. From the first,
the new religion set itself firmly against infanticide and abortion, and
won one of its most signal moral triumphs in driving underground and
greatly diminishing homosexual vice. Its encouragement of celibacy,
especially for those who followed the 'religious' vocation, was an
offset to its healthy influence on family life, and ultimately, as
Galton has shown, worked great mischief by sterilising for centuries
many of the gentlest and noblest in each generation; but this tendency
was adventitious to Christianity, and would never have taken root on
Palestinian soil. The cult of virginity has lasted on, with much else
that belongs to the later Hellenistic age, in Catholicism.

In the Middle Ages the population question slumbered. The miserable
chaos into which the old civilisation sank after the barbarian
invasions, the orgies of massacre and plunder, the almost total oblivion
of medical science, and the pestiferous condition of the medieval walled
town, which could be smelt miles away, averted any risk of
over-population. Families were very large, but the majority of the
children died. Millions were swept away by the Black Death; millions
more by the Crusades. Such books as that of Luchaire, on France in the
reign of Philip Augustus, bring vividly before us the horrible condition
of society in feudal times, and explain amply the sparsity of the
population.

The early modern period contains another notable example of a sudden and
unaccountable decline in population. The scene is Spain, which, after
playing an active and very prominent part in the world's history, sank
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