At first sight this might appear to falsify the law of population
enunciated by Malthus. Malthus maintained that population tended to
increase beyond the means of subsistence; that three checks constantly
operated to limit population--vice, misery, and moral restraint: vice,
due largely to diseased conditions, misery, due to poverty and want, and
moral restraint due to a dread of these. I shall show later that nothing
has been said or written to add to or take away from the truth and force
of these great principles, but, that the moral restraint of Malthus has
been practised to an extent, and in a direction of which the great
economist never dreamt. By moral restraint in the limitation of families
Malthus meant only delayed marriage. In so far as men and women
abstained from, or delayed their marriage, on the ground of inability to
support a family, they fulfilled the law, and followed the advice of
Malthus. Continence without the marriage bond was assumed; incontinence
was classed with another check vice.

Contrary to the expectations arising out of the famous progressions,
wealth and production have increased and the birth-rate has decreased.
It is the purpose of this work to show what are the causes that have led
to this decline, that those causes are not equally operative through all
classes of the people, and that the chief cause of the decline of the
birth-rate is the desire on the part of both sexes to limit the number
they have to support and educate. The considerations that lead up to,
and, to some extent, justify this desire, will be discussed later.

The fact remains that an increasingly large number of people have come
to the conclusion that the burden and responsibility of family
obligations limit their enjoyments in life, their ambition, and even
their scope for usefulness, and have discovered, through the spread of
physiological information, means by which marriage may be entered upon