There are several major themes to the novel. The theme of technology as philosophy describes the belief that everything is possible and that technology allows people to control all aspects of their lives. This view is contradicted throughout the novel by events. By the end of the novel, Walter's belief in technology is severely tested.
The theme of fate versus coincidence also appears throughout the novel. The events in Homo Faber are presented in such a way so they appear to be either a string of coincidences resulting in an unlikely outcome, or a sequence of predestined actions and decisions leading to a necessary outcome. This dichotomy is reflected in a larger series of seeming antinomies: faith or reason, modern knowledge or ancient beliefs, free will or predestination. Walter never resolves this conflict.
The theme of travel plays an important role in the novel. Using many modes of transportation, Walter is constantly on the move, visiting multiple continents, almost a dozen countries, and dozens of cities, for business and pleasure. This constant travel underscores Walter's sense of dislocation; he has no family, no real home, and no real country. Through travel, Walter is able to avoid permanent connections, to escape responsibilities, and to remain completely unknown and unjudged.