The story of Proclus in Arabic is similar ways to that of the Arabic Plotinus. It would seem that there was an original version of Proclus’ Elements of Theology in Arabic, which is preserved now only in the form of later partial redactions and re-workings (on this see most recently Wakelnig 2006; the pioneering study is Endress 1973). Again, the most famous text to derive from the Arabic Proclus is a pseudo-Aristotelian work: the Book on the Pure Good, known in Latin as the Book of Causes (Liber de Causis). Though not particularly influential in Arabic, the Book of Causes was a major source for Neoplatonic ideas in the Latin west. It was announced as being based on Proclus, and not Aristotle, by none other than Thomas Aquinas.