The so-called “Theology of Aristotle” was still considered by Farabi to be a genuine work. In Neo-Platonic fashion, and with some attempt at adaptation to the Muslim faith, he seeks to demonstrate that Plato and Aristotle harmonize with one another. The need which he experiences is not for a discriminating criticism, but for a conclusive and comprehensive view of the world; and the satisfaction of this need,—which is rather a religious than a scientific one,—induces him to overlook philosophic differences. Plato and Aristotle must differ from each other only in method, in phraseology, and in relation to practical life: their doctrine of wisdom is the same. They are the ‘Imāms’ or ‘highest authorities’ in philosophy; and seeing that they were two, independent, original minds, the authority which is constituted by their agreement has more validity in the eyes of Farabi than the faith of the whole Muslim community, who with blind confidence follow the guidance of one. 4. Farabi is counted among the physicians, but he seems not to have been in actual practice. He was entirely devoted to the spiritual healing art. Purity of Soul he denominated the condition and fruit of all philosophizing, and he demanded love of truth even though it should oppose Aristotle. Then the judgment has to be trained by means of Geometry and Logic for the study of physical and mental science. Farabi, however, pays but little heed to the separate branches of study: his powers are concentrated on Logic, Metaphysics, and the principles of Physics. Philosophy for him is the science of all Being as such, in the acquisition of which science we come to resemble the Godhead. It is the one, all-embracing science, which pictures the world to us as a Universe. Farabi’s charge against the Dialecticians is, that they employ as a basis for their demonstrations the deliverances of ordinary consciousness without testing them; and the Natural-Philosophers he blames for continually occupying themselves merely with the effect of things, and thus never getting beyond the contrasts of worldly phenomena by attaining to a unified conception of the All. He would confront the former by setting Thought on a proper foundation; and in opposition to the latter he would thoroughly investigate the subject of the One First Cause of all that exists. Consequently we shall be taking the best way to do justice to his historical and dogmatic position, if we endeavour to give some account, first of his Logic, next of his Metaphysics, and finally of his Physics and Practical Philosophy.