n, that such
restraints have been established by a certain amount of forethought as
regards the future, or a certain calculation as to social advantages to
be gained by limiting the number of children, a check on natural
fertility is established. But a sudden accession of prosperity--a sudden
excess of work and wages and food--sweeps away this check by apparently
rendering it unnecessary; the natural reproductive impulse is liberated
by this rising wave, and we here see whatever truth there is in the
statement that prosperity means a high birth-rate. In reality, however,
prosperity in such a case merely increases fertility because its sudden
affluence reduces a community to the same careless indifference in
regard to the future, the same hasty snatching at the pleasures of the
moment, as we find among the most hopeless and least prosperous
communities. It is a significant fact, as shown by Beveridge, that the
years when the people of Great Britain marry most are the years when
they drink most. It is in the absence of social-economic restraints--the
absence of the perception of such restraints, or the absence of the
ability to act in accordance with such perception--that the birth-rate
is high.

Arsene Dumont seems to have been one of the first who observed this
significance of the oscillation of the birth-rate, though he expressed
it in a somewhat peculiar way, as the social capillarity theory. It is
the natural and universal tendency of mankind to ascend, he declared; a
high birth-rate and a strong ascensional impulse are mutually
contradictory. Large families are only possible when there is no
progress, and no expectation of it can be cherished; small families
become possible when the way has been opened to progress. "One might
say," Dumont puts it, "that invisible valves, like those which direct
the circulation of the blood, have been placed by Nature to direct the
current of human aspiration in the upward path it has prescribed." As
the proletariat is enabled to enjoy the prospect of rising it comes
under the action of this law of social capillarity, and the birth-rate
falls. It is the effort towards an indefinite perfection, Dumont
declares, which justifies Nature and Man, consoles us for our griefs,
and constitutes our sovereign safeguard against the philosophy of
despair.[127]

When we thus interpret the crude facts of the falling birth-rate,
viewing them widely and calmly in connection with the other social fa