From 《
红楼梦》 (Dream of the Red Chamber) by
曹雪芹 (Qing dynasty), chapter 5, a couplet hanging in Ning Guofu's reception hall:
世事洞明皆学问,
人情练达即文章 ('seeing through worldly affairs is all scholarship; mastery of human feelings is itself fine writing'). Famous as an ironic symbol: it voices a worldly, practical ethic that the novel ultimately treats with ambivalence.