When Tom confronts Gatsby about his affair with Daisy, he makes hypocritical reference to “family life and family institutions,” even though he’s guilty of infidelity himself. This reference to traditional institutions symbolizes the challenge to tradition that is at the heart of this modernist novel. Gatsby’s modern dream is to be the upstart who topples tradition and wins the girl of his dreams, despite the fact that he’s not from an old, established family. Furthermore, Tom compares the affair between Gatsby and Daisy to the idea of interracial marriage, another prospect that represents a challenge to tradition and, in Buchanan’s mind, civilization.