The first story of the book, The Sisters, was rewritten to fit more perfectly the start of a larger collection. In the final version, three words are italicised on the first page: paralysis, gnomon, and simony. This is typical of Joyce's style. It is in keeping with his sense of realism that these foreign sounding words would stick in the head of a young child. But the words simultaneously take on a symbolic value that identifies the thematic contents of the book.
Simony is a religious term taken from the Catechism that denotes the buying of ecclesiastical favours. Joyce, particularly in Grace, is concerned with religious hypocrisy, but he also means the term to refer to a more widespread materialist corruption of the spirit. This phenomenon is most obviously manifested in a secular form in Ivy Day in the Committee Room, where the substance of the Irish Movement is exploited by its own members for motives of personal greed. This conflict between money and integrity resonates throughout the collection.
Gnomon is a term taken from Euclidean geometry that refers to the smallest part of a parallelogram. Critics have taken this as a reference to Joyce's economy of style (where the part signifies the whole - thus the lack of obvious beginnings and endings in the stories). The stories in Dubliners are brief narratives in which he makes his points through the tiny details of gesture in his characters, or through the even subtler movements of a character's consciousness. But the word gnomon also denotes an indicator, and is most commonly used in reference to the sun-dial, where the gnomon indicates time. In the same first paragraph the child recalls the self-conscious realisation of the priest: "I am not long for this world." Later, we are told that for Eveline, "her time was running out". The epiphanies (moments of spiritual revelation) around which the stories are based aim either to raise the trivial existence of his characters to a level of conscious significance for the reader, or to illustrate an instant of self-realisation in the characters themselves.
The stories in Dubliners find their most strongly binding aspect in the theme of paralysis. Joyce talked about the physical phenomenon of hemiplegia to symbolise a paralysis in his characters that extended into the psychological, the social and the spiritual as well as the physical realm. His art, in its criticism of this state of paralysis, is, by implication, a defence of active and fulfilling Life.