One theme of the trilogy is certainly the universality of an individual's experience. The unknowable and alien Chinese peasant is transformed here into an unfeared and universal "everyman." Less consciously expressed is the theme of the salutary effect of hard work close to the earth, and the corrupting nature of sloth and luxury. But the most obvious theme is surely the continuity of life itself, the sweeping inevitable cyclical nature of life, where death is counterbalanced by birth, sadness by joy. This cycle is also evident when, after Wang the Tiger has abjured the ideals of his father for a military career, his son Yuan rejects his father to embrace again the land. As opposed to some of her later more
propagandistic novels, the message of House of Earth is primarily nothing more sophisticated than the universal ebb and flow of life; life as it simply is, people as they simply are.

But the theme of hard work as panacea was emotionally charged for many Depression-ridden American readers of the early 1930s, for as W. J. Stuckey points out, the economic misery of the 1930s was a result of the extravagant 1920s when Americans abandoned their time-honored virtues of hard work, thrift and sobriety. In this way Buck provided, probably unintentionally, the ready public with a deeply satisfying solution — "Go back to the earth" — to a complex problem. This, plus the sheer escapism of reading about problems somewhere else, probably accounts for much of the popularity associated with The Good Earth and its sequels.