6. According to August Müller the theory of Ibn Khaldûn is in conformity with the history of Spain, West Africa and Sicily, from the eleventh to the fifteenth century,—from the study of which, in fact, it was taken. His own historical work is a compilation, it is true. In detail he is often at fault, when he criticizes tradition with the help of his theory; but there is an abundance of fine psychological and political observation in his philosophical Introduction, and as a whole it is a masterly performance. The ancients never dealt thoroughly with the problem of History. They have bequeathed to us great works of art in their historical compositions, but no philosophical establishment of History as a Science. That mankind, though existing from all eternity, long failed to attain to much of the higher civilization, was explained by elementary occurrences, such as earthquakes, floods, and the like. On the other hand Christian philosophy regarded History with its vicissitudes as the realization of, or the preparation for, the kingdom of God upon the earth. Now Ibn Khaldûn was the first to endeavour,—with full consciousness and in a statement amply substantiated,—to derive the development of human society from proximate causes. The conditions of race, climate, production of commodities, and so on, are discussed, and are set forth in their effect upon the sensuous and intellectual constitution of man and of society. In the course which is run by civilization he finds an intimate conformity to Law. He searches everywhere for natural causes, with the utmost completeness which was possible for him. He also asserts his belief that the chain of causes and effects reaches its conclusion in an Ultimate Cause. The series cannot go on without end, and therefore we argue that there is a God. But this deduction, as he calls it, properly means this,—that we are not in a position to become acquainted with all things and the manner of their operation: it is virtually a confession of our ignorance. Conscious ignorance is even a kind of knowledge; but knowledge should be pursued, as far as possible. In clearing the way for his new science, Ibn Khaldûn considers that he has merely indicated the main problems, and merely suggested generally the method and the subject of the science. But he hopes that others will come after him to carry on his investigations and propound fresh problems, with sound understanding and sure knowledge. Ibn Khaldûn’s hope has been realized, but not in Islam. As he was without forerunners, he remained without successors. But yet his work has been of lasting influence in the East. Many Muslim statesmen who, from the fifteenth century onwards, drove so many a European sovereign or diplomatist to despair, had studied in our philosopher’s school. 2. The Arabs and Scholasticism.