This study is a detailed textual examination of the word "parallax" in Ulysses. It distinguishes three levels of meaning for the word in the novel. In the first level, parallax functions as a character motif, a detail, first appearing in and conforming to the realistic surface of Bloom's inner monologue, whose meaning is what it tells of his crucial problems of identity. In the second, parallax functions as an integral part of the symbolic complex, lying outside of Bloom's perceptions, surrounding the emblem of crossed keys, symbol of, among other things, paternity and homerule, two major narrative themes. The third level involves parallax as a symbol informing the novel's overriding theme of the writing of Ulysses itself and of the relationship between the novel's representative life and artistic design.