its force generally, and, before we expose 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 to which, therefore, the ordinary moral sentiment does not attach in the same way that it does to the plainer and more direct applications.  Thus, if it can be shewn, as it undoubtedly can be, that smuggling falls under the head of stealing, and holding out false hopes under that of lying, the moralist need take no account of the lax moral sentiment which exists with regard to these practices, though, of course, in estimating the guilt of the individual as distinct from the character of the act, due allowance must be made for his imperfect appreciation of the moral bearings of his conduct.  This exception, as will be found in the next chapter, covers, and therefore at once justifies, a large proportion of the criticisms which, in the present advanced stage of morality, when the more fundamental principles have been already settled, it is still open to us to make.