sufficient apology for what, in itself, is the most unjust and unreasonable conduct. There is an obvious reason why custom should never pervert our sentiments with regard to the general style and character of conduct and behaviour, in the same degree as with regard to the propriety or unlawfulness of particular usages. There never can be any such custom. No society could subsist a moment, in which the usual strain of mens conduct and behaviour was of a piece with the horrible practice I just now mentioned. [Illustration] PART VI. Of Systems of MORAL PHILOSOPHY. CONSISTING OF FOUR SECTIONS. SECTION I. Of the questions which ought to be examined in a theory of moral sentiments. If we examine the most celebrated and remarkable of the different theories which have been given concerning the nature and origin of our moral sentiments, we shall find that almost all of them coincide with some part or other of that which I have been endeavouring to give an account of; and that if every thing which has already been said be fully considered, we shall be at no loss to explain what was the view or aspect of nature which led each particular author to form his particular system. From some one or other of those principles which I have been endeavouring to unfold, every system of morality that ever had any reputation in the world has, perhaps, ultimately been derived. As they are all of them, in this respect, founded upon natural principles, they are all of them in some measure in the right. But as many of them are derived from a partial and imperfect view of nature, there are many of them too in some respects in the wrong. In treating of the principles of morals there are two questions to be considered. First, wherein does virtue consist? Or what is the tone of temper, and tenour of conduct, which constitutes the excellent and praise-worthy character, the character which is the natural object of esteem, honour, and approbation? and secondly, by what power or faculty in the mind is it, that this character, whatever it be, is recommended to us? Or in other words, how and by what means does it come to pass, that the mind prefers one tenour of conduct to another, denominates the one right and the other wrong; considers the one as the object of approbation, honour, and reward, and the other of blame, censure, and punishment? We examine the first question when we consider whether virtue consists in benevolence, as Dr. Hutcheson imagines; or in acting suitably to the different relations we stand in, as Dr. Clarke supposes; or in the wise and prudent pursuit of our own real and solid happiness, as has been the opinion of others.