Critics have described Harris's abstract, experimental narratives as difficult to read, dense, complex, or opaque. Many readers have commented that Harris's essays push the boundaries of traditional literary criticism, and that his fiction pushes the limits of the novel genre itself. Harris's writing has been associated with many different literary genres by critics, including: surrealism, magic realism, mysticism and modernism. Over the years, Harris has used many different concepts to define his literary approach, including: cross-culturalism, modern allegory, epic, and Quantum Fiction. One critic described Harris's fictions as informed by "quantum penetration where Existence and non-existence are both real. You can contemplate them as if both are true."