4. In his logical writings Ibn Baddja hardly departs from Farabi. Even his physical and metaphysical theories agree generally with the views of the master. But perhaps the mode, in which he represents the history of the development of the human spirit and the position of man in knowledge and in life, may claim a measure of interest. There are two kinds of existence, according to his view,—one which is moved, and one which is not moved. That which is moved is corporeal and limited, but its everlasting movement cannot be explained by finite Body. On the contrary, in order to explain this endless movement, an unending power is needed, or an eternal essence, namely Spirit. Now while the corporeal or the natural is moved from without, and the Spirit, itself unmoved, confers movement upon the corporeal, the Soul-substance occupies a middle position, being that which moves itself. The relation between the natural and the psychical presents as little difficulty to Ibn Baddja as to his predecessors; but the great problem is this:—‘How are the Soul and the Spirit related to each other, that is to say in Man?’ 5. Ibn Baddja starts with the assumption that Matter cannot exist without some Form, while Form may exist by itself, without Matter. Otherwise, in fact, absolutely no change is thinkable, because that is rendered possible only by the coming and going of substantial Forms. These Forms then, from the hylic up to the purely spiritual, constitute a series, to which the development of the human spirit corresponds, in so far as it realizes the rational ideal. Man’s task is to comprehend all the spiritual Forms together; first the intelligible Forms of all that is corporeal, then the sensible-spiritual presentations of the Soul, next the human Spirit itself and the Active Spirit over it, and lastly the pure Spirits of the celestial spheres. By rising through successive stages from the individual and sensible, the presentation of which constitutes the material on which the Spirit operates, Man attains to the superhuman and the Divine. Now his guide in this process is Philosophy, or the knowledge of the universal, which issues from knowledge of the particular through study and reflection, aided however by the enlightening Spirit from above. Contrasted with this knowledge of the universal or the infinite,—in which Being, and becoming the object of cognition coincide,—all perception and presentation prove deceptive. Thus it is by rational knowledge, and not by religious and mystical dreaming, with the sensuous invariably clinging thereto, that the human Spirit arrives at perfection. Thinking is the highest bliss, for its very purpose is to reach all that is intelligible. But since that is the universal, the continued existence of individual human Spirits beyond this life cannot be assumed. It may be that the Soul,—which apprehends the particular in the life of sensuous-spiritual presentation, and notifies its existence in separate desires and