to all matters which belong to the sphere of what we commonly call morals, there are in every community some who approve of a given act, others who disapprove of it, yet others who regard it with indifference. In such a shifting sphere we cannot legislate with the certainty of carrying the whole community with us, nor can we properly introduce the word "crime," which ought to indicate only an action of so gravely anti-social nature that there can be no possibility of doubt about it.
It is, however, important to understand the marked national differences in the reaction to these slightly or dubiously anti-social acts, for such differences rest on ancient tradition, and are to some extent the expression of the genius of a people, though they are not the absolutely immutable product of racial constitution, and, within limits, they undergo transformation.
It thus happens that acts which in some countries are pursued by the law and punished as crime, are in other countries untouched by the law, and left to the social reaction of the community.
It becomes, therefore, of some importance to compare national differences in the attitude towards immorality, to find out whether the attempt to repress it directly, by law, is more effective, or less effective, than the method of leaving it to social reaction.