to
further social progress is not new. It has been practised with signal
lack of success for several thousand years. Therefore, if Social Hygiene
is really to progress among us on sane and fundamental lines, it is
necessary for us to realize clearly the mistakes of the past. Again and
again the blind haste of over-zealous reformers has led not to
progress, but to retrogression. The excellent intentions of such social
reformers have been defeated, not so much by the evils they have sought
to overcome, as by their own excesses of ignorant zeal. As our knowledge
of history and of psychology increases, we learn that, in dealing with
human nature, what seems the longest way round is sometimes the shortest
way home.

Among savages, and no doubt in primitive societies generally, the social
reaction against injurious or even unusual acts on the part of
individuals is regulated by the binding force of custom. The ruling
opinion is the opinion of all, the ruling custom is the duty for all.
The dictates of custom, even of ritual and etiquette, are stringent
dictates of morality binding upon all, and the breach of any is
equivalent to what we should consider a crime. The savage man is held in
the path of duty by a much more united force of public opinion than is
the civilized man. But, as Westermarck points out, in a suggestive
chapter on customs and laws as the expression of moral ideas, "custom
never covers the whole field of morality, and the uncovered space grows
larger in proportion as the moral consciousness develops.... The rule of
custom is the rule of duty at early stages of development. Only progress
in culture lessens its sway."[191] As a community increases in size and in
cultivation, growing more heterogeneous, it adheres rigidly to
fundamental conceptions of right and wrong, but in less fundamental
matters its moral ideas become both more subjective and more various. If
a man kills another man out of love to that man's wife, all civilized
society is of opinion that the homicide is a "crime" to be severely
punished; but if the man should make love to the wife without killing
the husband, then, although in some savage societies the act would still
have been a "crime," in a civilized society it would usually be regarded
as more properly a case for civil action, not for criminal action; while
should it come to be known that the wife had from the first been in love
with the man, and was married by compulsion to a husband w