The narrator pauses to reflect that the lives of the Tullivers and Dodsons must seem very “sordid” and insignificant. However, the narrator explains that it is necessary to depict this “oppressive narrowness” in order to understand the forces that have shaped Tom and Maggie's lives.
The narrator points out that the Tullivers' bankruptcy appalled the Dodsons because they saw poverty as a moral failing that threatened the respectability of the family. Their mantra was to be “rich and honest,” not “poor and honest.” For the Dodsons, doing the right thing for the Tullivers meant “correct[ing] them severely” for breaching standards of propriety.
The Dodsons’ lack of compassion for their relatives is a form of self-righteousness. In their understanding of the world, financial solvency is linked to morality. Thus, they believe they have the right to judge the Tullivers because they think that people who fail financially must have done so through lack of proper management.