This paper introduces an anonymous and undated Arabic version of Euclid’s Elements. It tries to determine its relationship to the textual history of the Arabic Elements as known today. The value of the version, the paper argues, is its close relationship to the works of the first known translator of Euclid’s Elements into Arabic, al-Ḥajjāj b.Yūsuf b.Maṭar, the light it sheds on philosophical debates surrounding the Elements, and the new textual basis (BooksI toIX with some lacunae) it yields for...