There have been always two different schemes or systems of morality current at the same time

From the evergreen writing of Adam Smith; The Wealth of Nations Book V, chapter I:

In every civilised society, in every society where the distinction of ranks has once been completely established, there have been always two different schemes or systems of morality current at the same time; of which the one may be called the strict or austere; the other the liberal, or, if you will, the loose system. The former is generally admired and revered by the common people: the latter is commonly more esteemed and adopted by what are called people of fashion. The degree of disapprobation with which we ought to mark the vices of levity, the vices which are apt to arise from great prosperity, and from the excess of gaiety and good humour, seems to constitute the principal distinction between those two opposite schemes or systems. In the liberal or loose system, luxury, wanton and even disorderly mirth, the pursuit of pleasure to some degree of intemperance, the breach of chastity, at least in one of the two sexes, etc., provided they are not accompanied with gross indecency, and do not lead to falsehood or injustice, are generally treated with a good deal of indulgence, and are easily either excused or pardoned altogether. In the austere system, on the contrary, those excesses are regarded with the utmost abhorrence and detestation. The vices of levity are always ruinous to the common people, and a single week’s thoughtlessness and dissipation is often sufficient to undo a poor workman for ever, and to drive him through despair upon committing the most enormous crimes. The wiser and better sort of the common people, therefore, have always the utmost abhorrence and detestation of such excesses, which their experience tells them are so immediately fatal to people of their condition. The disorder and extravagance of several years, on the contrary, will not always ruin a man of fashion, and people of that rank are very apt to consider the power of indulging in some degree of excess as one of the advantages of their fortune, and the liberty of doing so without censure or reproach as one of the privileges which belong to their station. In people of their own station, therefore, they regard such excesses with but a small degree of disapprobation, and censure them either very slightly or not at all.