In these last few chapters we shall see Croce himself at work on the new problems generated by his own system, trying "more rigidly to eliminate the last remnants of naturalism, and to put a stronger accent on the spiritual unity,"[1] yet constantly defending his conception of the spirit as the unity of distinctions, especially against the mystical tendencies of the new actual idealism. While never, in the course of his whole life, has he limited his activity to mere systematic thinking, during the last eleven years he has shown a more marked tendency to return from a philosophy, which is all a meditation of the formal problems of history, to those concrete works of history, by which he was started on his philosophical career; to return to them, however, with a mind in which the original uncertainty and obscurity has given place to a definite consciousness of the nature and purpose of history. The passage from the more philosophical to the more historical stage is marked by the publication of a fourth volume of the _Filosofia dello Spirito_, in which, under the title of _Teoria e Storia della Storiografia_, he collected a number of essays written between 1912 and 1913, containing an elaboration of the theory of history already expounded in the _Logica_. This volume does not form a new part of the system, but rather the natural conclusion of the whole work, since the problem which it discusses is the one towards which tended all his former inquiries into the forms of the spirit, into their concrete life which is development and history, and the consciousness of which is historical thought. But before proceeding to analyze this final form of Croce's theory of history, we shall give a rapid account of the rest of his intellectual activity from 1910 onward.