book 30 of the Metaphysics, all from the existing Syriac versions. He

was also the author of original commentaries on Aristotle’s Categories and the Isagoge of Porphyry.

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.

Most important in the fuller development of this neo-Platonic doctrine was the so-called _Theology of Aristotle_ which appeared in Arabic about 226 A.H. It was in fact an abridged paraphrase of the last three books (iv-vi) of the _Enneads_ of Plotinus made by Naymah of Emessa, boldly circulated and generally received as a genuine work of Aristotle. It might be regarded as a literary fraud, but it is quite possible that Plotinus was confused with Plato whose name appears in Arabic as _`Aflatun_, it seems indeed that this particular confusion was made by some other writers, and the translators accepted the current belief, maintained by all the neo-Platonic commentators, that the teaching of Aristotle and that of Plato were substantially the same, the superficial appearances of difference being such as could be easily explained away. By means of this _Theology_ the fully developed doctrine of the neo-Platonists was put into general circulation and combined with the teaching of Alexander of Aphrodisias and thus exercised an enormous influence on the philosophy of Islam in several directions. In the hands of the philosophers properly so called it developed an Islamic neo-Platonism which received its final form at the hands of Ibn Sina (Avicenna) and Ibn Rushd (Averroes), and in this form exercised a powerful influence over Latin scholasticism. Transmitted in another atmosphere it affected Sufism or Muslim mysticism, and was mainly responsible for the speculative theology which that mysticism developed. In a modified form some of the resultant principles gathered from these two sources finally entered into orthodox Muslim scholastic theology.

The main points of this neo-Platonic doctrine as it figures in Muslim theology present the teaching of the active intellect of _`aql fa``al_, the Agent Intellect of Alexander Aph. as an emanation from God, and the _`aql hayyulani_ or passive intellect in man only aroused to activity by the operation of this Agent Intellect, which is substantially the doctrine of Alexander Aph.: the aim of man is to attain a union or _ittisal_ in which his intellect becomes one with the Agent Intellect, although the means of attaining this union and the nature of the union differ in the doctrines of the philosophers and the mystics, as we shall see in due course.

Next to philosophy proper medical science is the most important heritage received by the Arabic world from Hellenism. But this science derived through an Alexandrian medium had a serious defect in the accretions which the later Egyptian school had added to the pure teaching of Galen and Hippocrates. As we have already noted this accretion is of a quasi magical character and shows itself in talismans, etc., and theories which are based on ideas which are now classed as “sympathetic magic.”

The real impetus came ultimately from transmitted Hellenism, but this influence was derived immediately from the Nestorians in philosophy proper, and from the Nestorians and the Zoroastrian school at Junde-Shapur in medicine. A good deal later comes the influence of the pagan school at Harran, which also had a neo-Platonic tendency. When the second Abbasid Khalif al-Mansur passed by Harran on his way to fight against the Byzantine Emperor he was astonished to observe the strange appearance of some of the citizens who came out to meet him, wearing their hair long and having close fitting tunics. When the Khalif asked whether they were Christians, Jews, or Zoroastrians, they replied that they were neither. He then enquired if they were “people of a book,” for it was only those who possessed written scriptures who could be tolerated in Muslim dominions; but to this they returned such hesitating and ambiguous replies that the Khalif at length felt convinced that he had discovered a colony of pagans, as was the case, and he ordered them to adopt some one or other of the “religions of the book” before his return from the war, or to suffer the penalty of death. At this they were greatly alarmed: some of them became Muslims, others Christians or Zoroastrians, but some declined to desert their traditional beliefs. These latter naturally had the most anxious time, wondering how they could contrive to evade the Khalif’s demands. At length a Muslim lawyer offered to show them a way out of the difficulty if they paid him a substantial fee for doing so. The fee was paid and he advised them to claim to be Sabians, because Sabians are mentioned in the Qur´an as belonging to a religion “of the book,” but no one knew who the Sabians were. There is a sect known as _Sabiyun_ or _Sabaean_, whose religion is a strange mixture of ancient Babylonian state worship, Christian Gnosticism, and Zoroastrianism, living in the mashe lands near Basra, but they had always been careful to keep their religious beliefs secret from all outsiders, and although they were no doubt the sect mentioned in the Qur´an under the name of _Sabiyun_ or _Sabians_, none could prove that the pagans of Harran were not also comprised under this term. The Khalif never did pass back by Harran, the pagans who had assumed the name of Sabian continued to use it, those who had become Christians or Zoroastrians reverted to their old faith and submitted to its new name; those who had become Muslims were obliged to remain so as the penalty of death lay upon any who became renegades from that religion.

The most distinguished of the _alumni_ of Harran was Thabit b. Qurra (d. 289 A.H.), a scholar familiar with Greek, Syriac, and Arabic, who produced many works on logic, mathematics, astrology, and medicine, as well as on the ritual and beliefs of the paganism to which he remained faithful. Following in his footsteps were his son Abu Sa`id Sinan, his grandsons Ibrahim and Abu l-Hasan Thabit, and his great grandsons Ishaq and Abu l-Faraj. All these specialized in mathematics and astronomy.

It seems that we ought to associate with Harran _Jabir b. Hayyan_ a perfectly historical character but of somewhat uncertain date, but believed to have been a pupil of the `Umayyad prince Khalid, who distinguished himself by his researches in chemistry. Many chemical treatises bear the name of Jabir and a great proportion of these are probably quite authentic. M. Berthelot in the 3rd volume of his _La chimie au moyen age_ (Paris, 1893) has made a careful analysis of the Arabic chemists and regards the whole material capable of division into two classes, the one a reproduction of the investigations of the Greek chemists of Alexandria, the other as representing original investigations, though based upon the Alexandrian studies in the first place, and all this original material he regards as due to the initiative of Jabir who thus becomes in chemistry very much what Aristotle was in logic. Berthelot publishes in this book six treatises claiming to be by Jabir, and these he regards as representative of all Arabic chemical material, the later investigators continuing in the lines laid down by this first investigator. For a long time the main object in view was the transmutation of metals, but at a later period chemistry enters into closer connection with medical work though never losing the metallurgical character which we imply when we speak of “alchemy.” The object in view of the Arabic students of alchemy does not appeal to the modern scientist, although the possibility of transmuting elements is no longer regarded as the impossible dream which it appeared to the chemists of the nineteenth century: and, at the same time, it is perfectly clear that with admitted limitations, the Arabic chemists were bona fide investigators, though not understanding correctly the results of the experiments they made.

All the texts published by M. Berthelot begin with the warning that the contents are to be kept strictly secret, and often contain a statement that some essential process is omitted in order that the unenlightened student may not be able to perform the experiments successfully, lest the wholesale production of gold should be a means of corrupting the whole human race. Undoubtedly the Arabic chemists did claim to have attained a knowledge of the means of transmuting the baser metals into gold but the histories contain various references which show that these claims were adversely criticised by many contemporary thinkers, and that a great many of the Arabic writers regarded chemistry, as it was then understood, as a mere imposture. More than once it was noted that the philosopher al-Farabi, who fully believed that it was possible to change other metals into gold and wrote a treatise on how it might be done, himself lived and died in great poverty, whilst Ibn Sina, who did not believe in alchemy, enjoyed modest comfort and could have commanded wealth had he been willing to accept it.

In the course of the middle ages various treatises by Jabir were translated into Latin, where his name appears as Geber, and exercised a considerable influence in producing a western school of alchemy. Before long many original alchemical works were produced in Western Europe and a considerable proportion of these were published under the name of Geber but are pure forgeries. As a result the personality of Geber took a semi mythical character and attempts have been made to account for the diverse and contradictory statements about his life and death, and about the country and century in which he lived by supposing that there were several persons who bore the name; but the fact seems to be that he early attained a position of great prominence as a chemical writer, and that later ages fathered on him a number of apocryphal productions. Berthelot considers that the best evidence associates him with Harran in the early part of the second century of the Hijra.