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.

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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 the State.—­Antiquity of the problem.—­The teaching of the ancients.—­Surgical methods already advocated.

A century has passed since Malthus made his immortal contribution to the supreme problem of all ages and all people, but the whole aspect of the population question has changed since his day.  The change, however, was anticipated by the great economist, and predicted in the words:—­“The history of modern civilisation is largely the history of the gradual victory of the third check over the two others” (vide Essay, 7th edition, p. 476).  The third check is moral restraint and the two others vice and misery.