[16] It was this which made Enouvier criticise sociology. He disagreed with its principles almost entirely. On this, see his notes to “_La Justice_,” Part VII. of _La Nouvelle Monadogie_, pp. 527-530. It was his doctrine of _idées-forces_ and its essential spiritualism or idealism which distinguished Fouillée’s attitude from that of these sociologists who were his contemporaries. It was the basis, too, of his trenchant criticisms of socialism, particularly its Marxian forms. Fouillée agrees with Comte’s doctrine that speculation or thought is the chief factor and prime mover in social change. For Fouillée the idea is always a force; and it is, in this connection, the supreme force. The history of action can only be understood, he asserts, in relation to the history of ideas. This is the central gospel of the _évolutionnisme des idées-forces_. The mental or spiritual is the important factor. This he opposes to the Marxian doctrine of economic determinism. Will is, he claims a greater reality than brute forces, and in will lies the essence of the human spirit. It is a will, however, which is bound up with reason and self-consciousness, and which is progressive in character. Summing up his work, _Histoire générale de la Philosophie_, Fouillée refers in his Conclusion to the idea of progress as having become the dominant note in philosophy. He looks upon the history of philosophy as, in some measure, witness to this. Above the ebb and flow of the varied systems and ideas which the ages have produced he sees an advance accomplished in the direction to which humanity is tending—perfect knowledge of itself or collective self-consciousness and perfect self- possession. This type of progress is not to be equated with scientific progress. He points out that in the development of philosophy, which is that of human reflection itself, two characteristics appear. The distinction of two kinds or aspects of truth is seen in philosophy; one section, dealing with logic, psychology, aesthetic and applied ethics, or sociology, approaches to a scientific character of demonstrability, while the other section, which constitutes philosophy in the strict sense of metaphysic, deals with ultimate questions not capable of proof but demanding a rational faith. Obviously the same kind of progress cannot be found in each of these sections. This must be realised when progress in knowledge is spoken about. He suggests, as illustrative of progress even in the speculative realm, the fact that humanity is slowly purifying its conception of God—a point for further notice in our last chapter.