As the great Doctors of the Church began often, without losing their virtue, by acquainting themselves with the sins of all mankind, out of which they extracted their own personal sanctity, so great artists often, while being thoroughly wicked, make use of their vices in order to arrive at a conception of the moral law that is binding upon us all. It is the vices (or merely the weaknesses and follies) of the circle in which they live, the meaningless conversation, the frivolous or shocking lives of their daughters, the infidelity of their wives, or their own misdeeds that writers have most often castigated in their books, without, however, thinking it necessary to alter their domestic economy or to improve the tone of their households.