enlightened public opinion concerning the measures which society can now,
at last, wisely undertake against the vices and evils which in the human
race accompany bodily self-indulgence and lack of moral stamina.

Till within five years, it was the custom in families, churches, and
schools, to say nothing about sex relations, normal or abnormal; and in
society at large to do nothing about the ancient evil of prostitution, to
provide neither isolation nor treatment for the worst of contagious
diseases, and to regard the blindness, feeble-mindedness, sterility,
paralysis, and insanity which result from those diseases as afflictions
which could not be prevented. The progress of medicine within twenty
years, both preventive and curative, has greatly changed the ethical as
well as the physical situation. The policy of silence and concealment
concerning evils which are now known to be preventable is no longer
justifiable. The thinking public can now learn what these evils are, how
destructive they are, and by what measures they may be cured or prevented.
With this knowledge goes the responsibility and duty of applying it in
defense of society and civilization.

This book is a sincere effort, first, to supply the needed knowledge of
terrible wrongs and destructions; and, secondly, to indicate cautiously
and tentatively the most available means of attacking the evils described.
It is an attempt to enlighten public opinion on one of the gravest of
modern problems--indeed, the very gravest, with the exception of the
warfare between capital and labor. The book is not intended for children,
or even for adolescents, but rather for parents, teachers, and ministers
who have to answer the questions of children and youth about sex
relations, or deal sympathetically with the victims of sexual vice.

All efforts to deal directly with sex relations in schools, churches, and