The novel explores many contrasting ideas. Indeed in many respects, the novel deals in opposites, variously conceived: Marsellus vs. Outland, Kitty vs. Rosamond, the quixotic vs. the pragmatic, the old vs. the new, the idea of the Professor as a scholar vs. his family relations, Indian tribes vs. the contemporary world of the 1920s, and the opposing social poles of the Professor vs. Lillian. Those opposites are not always clear-cut. Considering the ending, the novel can be viewed as devoid of a clear moral imperative.
Similarly, the comparisons between the modern world of sections III and I contrast with Tom Outland’s natural world in section II. Yet the confused judgments of the characters block these comparisons and obscure clear morals: Tom’s both elevates and appropriates nature, and the unsupported conclusions of Father Duchene pervert the true historical facts of the mesa culture. He assumes ‘Mother Eve’ was murdered for infidelity to her husband, but this would sharply contrast Tom’s view of the mesa as an idyllic space away from ‘the dirty devices of the world’. Accordingly The Professor’s House is generally analyzed as a critique of modernity—the Marselluses are consumed by the latest fashions, Mrs. St. Peter transfers her old love for her husband to a passion for her sons-in-law, science and the modern world corrupt St. Peter’s ideals of history and nature. Yet it is a failure to embrace modernity that nearly kills the Professor and brings him to the realization of his need for change. In his own speech, the knowledgeable professor puts forth numerous contradictions. He criticizes science for only making humans comfortable in front of his lecture hall students, yet with his daughter he lauds the promise of what science can do for man (Crane), and its superior value to money: “In Hamilton the correspondence between inner and outer has been completely destroyed: the dress-forms are deceptive; Rosamond's physical beauty clothes a spiritual emptiness; Louie's loud exterior covers an inner capacity for love and generosity. In Hamilton the failure of inner and outer to cohere leads to misunderstandings and to the characters' inability to make meaningful contact with one another".
The Professor's House was written in 1925, in post-war America. In a similar fashion to F. Scott Fitzgerald's The Great Gatsby, Cather narrates a story about the moral decline of a money-driven society.
Tom displays an Emersonian understanding of national identity. His sense of Americanness is connected to the land and its beauty, and he believes in a collective possession of this land and all of its history for all Americans. His anger at Roddy’s sale of the Native American artifacts to the German stems from a belief that they were a piece of American history, that they were of the land, and therefore nobody had the right to sell them, much less to a non-American. Tom’s ultimate experience of connection to an American identity comes during his night on the mesa alone after his confrontation with Roddy, when he discovers “the mesa was no longer an adventure, but a religious emotion” and, “It was possession”.
Louie’s sense of national identity in contrast centers on money and the economic greatness of the country. He spends liberally the income derived from Tom’s advances in engineering. Louie wears the source of his wealth proudly—the fact that his livelihood is derived from his wife’s deceased fiancé does not create tension between husband and wife nor between the couple and society. His announcement, “We have named our place for Tom Outland, a brilliant young American scientist and inventor, who was killed in Flanders, fighting with the Foreign Legion, the second year of the war, when he was barely thirty years of age,” displays his pride in and respect for his benefactor, and his recognition that Tom’s loyalty to the nation has brought Louie the monetary success he enjoys is representative of his understanding that America's economic success now takes precedence in defining the country and its people.
The professor is caught between the worldviews of Tom Outland and Louie Marsellus. He is resistant to change, idealistically holding onto Tom’s memory and an Emersonian ideality that impugnes material acquisitiveness. As Outland’s good friend and mentor, St. Peter feels it is his responsibility to make sure Tom’s will is properly executed. In this endeavor, he is torn between his love for Tom and his love for his daughter Rosamond, both of whom, the professor believes, have different views on how the money should be spent. When Mrs. Crane asks for his help in obtaining compensation for her husband for the patent on which he worked intimately with Outland, the professor says, “Heaven knows I’d like to see Crane get something out of it, but how? How? I’ve thought a great deal about this matter, and I’ve blamed Tom for making that kind of will”. On the one hand, he is digging his heels into the ground, resisting the shift from a love of the land to a love of its fruits, but he also has a sense of obligation which makes it difficult for him to ignore the role money, particularly Tom’s money, plays in his relationships and social life.
Cather’s endorsement of one worldview over another is debatable, as has been demonstrated by various critics. Walter Benn Michaels suggests that Cather sides with Tom Outland, in that the poetry of “the ‘picture’ of the cliff-dwellers’ tower, ‘rising strong, with calmness and courage’…marks in Cather the emergence of culture not only as an aspect of American identity but as one of its determinants”. From this perspective, Outland is Cather’s voice in the novel, advocating the close ties to the landscape as an expression of national identity. Contrarily, Sarah Wilson posits that Cather is instead critical of Tom’s nostalgia. “The cliff dwellings of the Blue Mesa once belonged to a now vanished culture, and no living Native American population has an indisputable claim on them…How, the novel queries, can a nation or individuals engage the history of a culturally and temporally other people?” However, Wilson does concede “the America of which Tom Outland speaks, the nation that treasures its ancient Southwestern heritage, at least allows for unique ways of being American”.