As in his other novels, Saramago's paragraph-long sentences, minimally interrupted by punctuation, challenge the reader to follow his continuous stream of thought, thus permitting a stronger sense of interaction and a more diverse interpretation of phrases and clauses. Keen that his reader should move easily back and forth between the present, the recorded and the imagined past, in this novel Saramago also freely shifts between past and present tenses, conveying the impression of the timelessness of the human imagination. This temporal fluidity is further emphasised by the strategic location of the proof-reader's flat within the precinct of the old Moorish fortress, a kind of watchtower from where the perception of past and present alternate according to the proof-reader's mood.
Beneath these speculations about the function and form of historical writing, we discover that the central concerns of Saramago's novel focus on our ability to distinguish truth from falsehood, to differentiate between reliable and suspect historical reporting, and the difficulty of drawing the frontier between the two, or in Saramago's own words: "The truth is that history could have been written in many different ways and this idea of infinitude and variation are the essence of my writing. The possibility of the impossible, dreams and illusions, are the subject of my novels."