This volume presents the first complete edition of Oxford, MS Marsh 539, a hitherto unpublished Philosophy Reader compiled anonymously in the eastern Islamic world in the eleventh century. The compilation consists of texts on metaphysics, physiology and ethics, providing excerpts from Arabic versions of Greek philosophical works (Aristotle, Plotinus, Galen), and works by Arabic authors (Qusta ibn Luqa, Farabi, Miskawayh). It preserves fragments of Greek-Arabic translations lost today, including Galen's On my own Opinions, the Summa Alexandrinorum, and Themistius on Aristotle's Book Lambda....