Magister Jacobus de Ispania, Author of the Speculum Musicae. By Margaret Bent

Abstract

The surviving texts of medieval treatises, together with their ‘metadata’ (prohemiums, explicits, marginalia, etc.) are often the richest sources of information about their authors. Unfortunately, the ‘Jacobus’ who completed a monumental Speculum musicae in the 1320s is remarkably cagey about his identity, limiting himself to indicating in the Prohemium that his first name may be obtained by forming an acrostic from the first letters of each of the seven books that comprise the treatise. Alas, for a long time readers did not connect the litterae (albeit with at least one important exception cited below) and misread an explicit in the only complete manuscript copy of the Speculum, with the result that the treatise was attributed to Jacobus’s contemporary Johannes de Muris from the sixteenth to the twentieth centuries. It was only in the 1920s that the acrostic was finally resolved, pointing to ‘Jacobus’ as the author of the treatise. Passing references to liégeois chant melodies in the tonary of Book VI were taken to imply that Jacobus spent the final years of his life in Liège. This speculation led Roger Bragard to formulate a new one in the 1950s—namely, that because it was relatively common at that time to retire in one’s place of origin, Liège was also the likely city of Jacobus’s birth. Since then, the Speculum musicae has been generally ascribed to a ‘Jacques de Liège’ with more or less conviction, perhaps due to the lack of credible alternatives rather than to the strength of Bragard’s argument.