Replication Under Constrant: Selective Revision in Marcel Duchamp's Nude Descending a Staircase No. 3

Marcel Duchamp's Nude Descending a Staircase, No. 3 (1916) was produced at the request of Walter Arensberg as a copy of the 1912 painting and executed using a photographic enlargement of the earlier work. These conditions impose strong constraints on deviation. This paper examines how those constraints shape the formal differences between the two paintings, arguing that while most changes reflect mechanical clarification, a specific set of recurring arc-like forms undergoes selective revision. The localized nature of this divergence invites closer attention to intentional intervention under conditions otherwise designed to suppress invention.