The translation of literary prose involves more than matching lexical meanings: it also reorganizes relations among rhetorical form, cultural reference, speakers, and implied readers. This article investigates how two English versions of the preface and Chapter Four of Saʿdi’s Gulistan reconfigure these relations and asks whether Lacanian accounts of the signifying chain and lack can clarify the limits of semantic equivalence. Using a qualitative, context-sensitive comparison of Francis Gladwin’s nineteenth-century version and an edition based on Edward Rehatsek’s translation, the study examines culturally marked expressions, shifts in evaluative meaning, metaphor, address, and narrative irony. The analysis distinguishes empirically observable differences between texts from the structural lack theorized by Lacan. Several passages preserve the narrative or ironic function despite lexical and phonological change; others redistribute cultural information or alter an expression’s evaluative force. The evidence therefore supports a differentiated, rather than absolute, account of equivalence. Lacan’s concepts prove useful in resisting the assumption of a fully self-identical meaning residing in the source, but they cannot serve as automatic explanations for omissions, additions, or individual translators’ decisions. The article proposes a three-level analytic distinction among textual shifts, function-specific equivalence, and theoretical claims about signification.