The obstacles to be encountered by the distinction between the history of historiography and that of the _practical tendencies,_ or tendencies of the _social and political spirit,_ are more intricate. These indeed become incorporated with or at least leave their mark upon the works of historians; but it is just because we can only with difficulty perceive the line of demarcation that it is indispensable to make it quite clear. Such tendencies, such social and political spirit, belong rather to the matter than to the theoretical form of history; they are not so much historiography as history in the act and in its _fieri._ Machiavelli is a historian in so far as he tries to understand the course of events; he is a politician, or at least a publicist, when he posits and desires a prince, founder of a strong national state, as his ideal, reflecting this in his history. This history, in so far as it portrays that ideal and the inspiration and teaching that accompany it, here and there becomes fable (_fabula docet_). Thus Machiavelli belongs partly to the history of thought in the Renaissance and partly to the history of the practice of the Renaissance. Nor does this happen solely in political and social historiography, but also in literary and artistic, because there is not perhaps a critic in the world, however unprejudiced and broad in his ideas, who does not manifest tendencies in the direction of a literary renovation of his epoch together with his actual judgments and reconstructions. Now to the extent that he does this, even if it be in the same book and on the same page or in the same period, he is no longer a critic, but a practical reformer of art. In one domain of history alone is this pacific accompaniment of interpretations and aspirations impossible--in the history of philosophy, because when, as here, there is a difference between historical interpretation and the tendency of the philosopher, the difference reveals the insufficiency of the interpretation itself: in other words, if the theory of the historian of philosophy is at war with the theories of which he claims to expound the history, his theory must be false, just because it does not avail to justify the history of the theories. But this exception does not annul the distinction in other fields; indeed, it confirms it, and is not an exception in the empirical sense, as it appears to be: thought distinguishes and is distinguished from sentiment and will, but it is not distinguished from itself, precisely because it is the principle of distinction. A methodological corollary of this distinction between history of historiography and history of practical tendencies is that the introduction into the first of considerations belonging to the second is to be held erroneous. Here I think Fueter has sinned to some extent in the book to which I have already referred, where he divides his material into humanistic, political, party, imperial, particularist,