Again, there can be little doubt of the vast influence exercised on
morals by human law and institutions. It is well known to those who
are at all acquainted with the life of the poor in large towns, that
in many cases conscience is mainly informed by positive law. But all
that human law can do is to secure a minimum of morality[418]. No
doubt it is true that indirectly positive law can do something more
than this, because good citizens will abstain from all actions which,
in however remote a degree, are likely to bring them into collision
with the law. But in the main it is true to say that what law can
secure is the observance on pain of punishment of a minimum moral
standard, which itself shifts with the public opinion of society,
rising as it rises, falling as it falls.