e men to this danger, we ought to
have some adequate justification. But there is also the speculative
ground that any given society, and indeed mankind generally, has been
engaged for ages in feeling its way, instinctively or semi-consciously,
towards a solution of the self-same problems which the philosopher is
attempting to solve consciously and of set purpose. That, on the whole,
a society has solved these problems in the manner best suited to its
existing needs and circumstances may fairly be taken for granted, and,
even where the ethical stand-point of the reformer is very superior to
the stand-point of the society which he wishes to reform, he will be
wise in endeavouring to introduce his reforms gradually, and, if
possible, in connexion with principles already acknowledged, rather than
in attempting to effect a moral revolution, the ultimate results of
which it may be impossible to foresee. The work of the moralist is,
therefore, best regarded as corrective of, and supplementary to, the
work which mankind is constantly doing for itself, and not as
antagonistic to it. The method is the same in both cases: only it is
applied semi-consciously, and merely as occasions suggest it, in the one
case; consciously and spontaneously in the other. In both cases alike
the guiding principle, whether of action or of speculation upon action,
is the adaptation of conduct to surrounding circumstances, physical and
social, with a view to promote, to the utmost extent possible, the
well-being of the individual and of the society of which he is a member.
Where the interests of the individual and of the society clash, society,
that is to say, a man's fellow-citizens, usually approves, as we saw in
the last chapter, of the sacrifice of individual to social interests, a
course of conduct which is also, on reflexion, usually stamped by the
individual's own approbation, and hence we may say briefly that their
tendency to promote or impair the welfare of society is the test by
which, in different ways, all actions are estimated alike by the
philosopher, in his hours of speculation, and by the community at large,
in the practical work of life.

In laying down the principle that the presumption of the moralist should
always be in favour of existing rules of conduct, I intimated that there
was one exception to this principle. The exception includes all those
cases which are legitimate, though not obvious, applications of existing
rules, and t