It is indeed also the “universal subject” that Kant has studied in his _Critic of Pure Reason_. But Kant’s method is altogether abstract and metaphysical, the universal subject of which he seeks the laws is a human mind “in itself,” considered in its essence. Comte, on the contrary, represents the universal subject as a concrete unity, which realized itself in time. For him, the study of the mental functions characteristic of man only becomes positive when it is carried out from an historical and sociological point of view. That is why the discovery of the law of the three States is an event of capital importance. It inaugurates the positive science of humanity, which was an indispensable condition for positive philosophy to be established. It marks the time when, all phenomena being henceforth studied after the same method, the “perfect logical coherence” is definitely assured. This law of social dynamics is the corner-stone of the whole positive system. FOOTNOTES: [10] Cours de philosophie positive, I, 19 (5e edition, Paris, 1892). [11] Cours, VI, 786. [12] Pol. pos. IV, appendice, p. 77. [13] Cours, I. 3. [14] Cours, I. 6. [15] Cours IV, 526. [16] Cours IV, 548. [17] Cours, IV, 554-5. [18] Pol. pos., IV. Appendix, p. 144. [19] Correspondence de H. Comte avec John Stuart Mill. Lettre du 5 avril 1842, p. 51. [20] Cours, V. 573-5. [21] Cours, IV, 523. [22] Cp. infra, book II, chap. V, p. CHAPTER III THE CLASSIFICATION OF THE SCIENCES According to the law of the three States, all our conceptions in the different orders of knowledge, begin by being theological, pass through the metaphysical transition, and end by becoming positive. If this evolution were terminated at the presented time, the philosophy which Comte wishes to found would be _ipso facto_ established. But we are far from such a state of things. On the contrary, the three modes of thought theological, metaphysical, and positive, coexist, still to-day, even in the most cultivated minds. In a different measure, all lack the “logical coherence.” Even in those sciences where the positive method has been finally and for a long time established, in physics, and in chemistry, for instance, we observe undoubted traces of the metaphysical spirit. To a still greater degree this spirit is manifested in what are called the moral and social sciences. Nevertheless, this “incoherence” cannot last. Now that the positive spirit has assumed full consciousness of itself, it is possible to proceed with a systematic purification, which will disentangle it from the theological and metaphysical spirit.