The 9th century Arabic work called Kalām fī maḥḍ al-khayr, known as the Liber de causis in its 12th century Latin translation, is often times considered in relation to its major Greek source, The Elements of Theology of the great Neoplatonist Proclus, or in relation to its broad use by philosophers and theologians of the Latin tradition. In the Arabic tradition it was considered part of the “metaphysics file” (Zimmermann) of philosophical teachings from Aristotle, Plotinus, Proclus, Alexander and more. In this lecture, Professor Richard Taylor proposes to reconceptualise the Kalām fī maḥḍ al-khayr as a work conceived as a supplement to the (Plotinian) “Theology of Aristotle” in which portions of Proclus are used to explicate further the cosmological metaphysics of “Aristotle”.