Read the last long paragraph in the section of Shaw's preface to "Major Barbara" titled "The Gospel of St. Andrew Undershaft." In this passage, Shaw discusses the fallacy of regarding some money as "clean" and other money as "dirty." He also criticizes well-educated and well-meaning people who do not understand the lesson that Barbara is learning about social responsibility, and who wear "Thomas Hood shirts" while underpaying their own servants. (Hood was a 19th-century poet whose most famous poem is "The Song of The Shirt," a sort of depressing rally cry for underpaid workers in clothing factories. To wear a Thomas Hood shirt is to arrange the surface details of one's life in a way that suggests one has deep feeling for those less fortunate; Shaw hints, however, that such a style may be a sham.) Setting aside all the jokes in the play, what is Shaw really saying, seriously, about the ideal organization of society and of human beings' use of resources?