ltogether;
while, on the other hand, the very qualities which make a man a social
burden, a criminal, a pauper, or a drunkard--improvidence and defective
inhibition--ensure that his fertility will be unrestrained, except by
the checks of biological law. And it now comes about that the good
citizen, who curtails his family, has the defective offspring of the bad
citizen thrown upon his hands to support; and the humanitarian zeal,
born of Christian sentiment, which is at flood-tide to-day, ensures that
all the defectives born to the world shall not only be nursed and
tended, but shall have the same opportunities of the highest possible
fertility enjoyed by their defective progenitors.

A higher and nobler human happiness is attainable only through social
evolution, and this comes from greater freedom of thought, from bolder
enquiry, from broader experience, and from a scientific study of the
laws of causation. What "is" becomes "right" from custom, but with our
yearnings for a higher ideal, sentiment slowly yields to the logic of
comparison, and, often wiping from our eyes the sorrows over vanishing
idols, we behold broader vistas of human powers, possibilities, duties,
and destiny.

As the proper study of mankind is man, influenced wholly by a desire to
be useful to a society to which I am indebted for the pleasures of
civilised life, I offer this brief volume as a comment on a phase of the
social condition of the times, and as my conclusions regarding its
interest for the future.

* * * * *

CHAPTER I.

THE PROBLEM STATED.

_The spread of moral restraint as a check.--Predicted by Malthus.--The
declining Birth-rate.--Its Universality.--Most conspicuous in New
Zealand.--Great increase in production of food.--With rising food
rate falling birth-rate.--Malthus's checks.--His use of the term "moral
restraint."--The growing desire to evade family obligations.--Spread
of physiological knowledge.--All limitation involves self
restraint.--Motives for limitation.--Those who do and those who do not
limit.--Poverty and the Birth-rate. Defectives prolific and propagate
their kind.--Moral restraint held to include all sexual interference
designed to limit families.--Power of self-control an attribute of the
best citizens.--Its absence an attribute of the worst.--Humanitarianism
increases the number and protects the lives of defectives.--The ratio of
the unfit to the fit.--Its dangers to