The Book of Causes

One of the central documents in the dossier on Neo-Platonism in the Middle Ages is, unquestionably, the Liber de causis. Although doubts linger about the origin and authorship, no one would think of minimizing its doctrinal importance in the history of medieval metaphysics. Slipped into the catalogue the Arabs had of Aristotle's works, the Liber became, together with the Theology of Aristotle, one of the principal sources of the eclectic tendency of Arabic and Jewish metaphysics.

The Latins of the 13th Century, who did not have access to the Theology of Aristotle, did have knowledge of the Liber de causis thanks to the translation made by Gerard of Cremona in Toledo. Circulated under Aristotle's name, this opuscule allowed the medievals to fill the metaphysical lacunae the authentic works of the Stagirite presented vis-a.-vis the vision of the world inspired by the great monotheistic religions.
From the Introduction