The Jacobite translators come on the scene after the Nestorians. Amongst the Jacobites translating from Syriac to Arabic we find _Yahya b. Adi_ of Takrit (d. 364), a pupil of Hunayn, who revised many of the existing versions and prepared translations of Aristotle’s Categories, Sophist. Elench., Poetics, and Metaphysics, Plato’s Laws and Timæus, as well as Alexander of Aphrodisias’ commentary on the Categories and Theophrastus on the Moralia. The Jacobite _Abu `Ali Isa b. Zaraah_ (d. 398) translated the Categories, the Natural History, and the _de partibus animalium_, with the commentary of John Philoponus. This is a convenient place to summarize briefly the range of Aristotelian material available to Arabic students of philosophy. The whole of the logical Organon was accessible in Arabic, and in this were included the Rhetoric and Poetics, as well as Porphyry’s _Isagoge_. Of the works on natural science they had the _Physica_, _de coelo_, _de generatione et corruptione_, _de sensu_, the _Historia animalium_, the spurious _Meteorologia_, and the _de anima_. On mental and moral science they had the _Metaphysics_, the _Nicomachæan Ethics_ and the _Magna Moralia_. Strangely enough the _Politics_ was not included in the Aristotelian canon, its place being taken by Plato’s _Laws_ or _Republic_. Besides these the Arabic students accepted as Aristotelian a _Mineralogy_, of which we have no knowledge, and a _Mechanics_. Of these the logical Organon always remained the basis of a humane education, side by side with the indigenous study of grammar, and this essentially logical basis of education seems to have been influenced by the example of the existing system developed amongst the Syrians, although it must be remembered a similar system was developed quite independently in Latin scholasticism prior to the earliest contact with the Arabic writers. The Aristotelian logic has always remained an orthodox and generally accepted science. The philosophical and theological controversies and the developments produced by the Arabic philosophers centred mainly in questions of metaphysics and psychology, and so were particularly concerned with the 12th book of _Metaphysics_ and the treatise _de anima_, more especially the 3rd book. As we have already noted the psychology of Aristotle was interpreted in the light of Alexander of Aphrodisias’ commentary, and thus received a theistic and supernatural colouring which receives its fuller development in neo-Platonic teaching.