  Apart from brief opening and closing remarks, Discourse on the Soul (Abu Rida 1950, 272–80; also D’Ancona 1996, Genequand 1987, Jolivet 1996) consists entirely of supposed quotes from Greek authorities – Plato, Pythagoras, and Aristotle – about the nature of the soul. The actual sources used are unclear, though the Republic is the ultimate source for a section describing Plato’s tripartite soul. The section on Aristotle is a fable about a Greek king, and has nothing to do with any extant Aristotelian work. The tenor of these remarks is hortatory, ascetic and even visionary: our task is to cleanse our souls from the “stains” that adhere to it from the body, and to ascend through the heavenly spheres, ultimately to the “world of the intellect” where it will reside in “the light of the Creator.” The soul in question here would seem to be the rational soul: the lower parts of Plato’s tripartite soul (the irascible and concupiscent parts) are described as faculties seated in the body.  The point of this psychological doxography is not unlike that of Incorporeal Substances: the soul is a “simple substance,” separate from body. Indeed this is presented as the overall message of the treatise in al-Kindi’s closing remarks.