These passions and volitional habits are not rigidly fixed, for nothing in the field of facts is rigidly fixed. As the bed of the river regulates the course of the river and is at the same time continuously modified by it, so is it with the passions and volitional acts, which reality keeps forming and modifying, and in modifying, forms anew and in forming modifies. For this reason there is always something arbitrary in defining habits as though they corresponded to a distinct and limited reality; and for this reason the concepts of them are arbitrary and empirical. Habits are not categories, nor do they give rise to distinct concepts; but they are the like in the unlike, unlike, itself also, in itself, although discernible in a certain way from other groups of dissimilar facts. Their importance is great, because they constitute, as it were, the bony structure of the body of reality. In them _individuality_ understood as an empirical concept, has its foundation, for which, if it be not substance, neither is it a complex of casually divergent states. [Sidenote: _The control of the passions in so far as they are volitional habits._] The nature of the passions as volitional habits to be both fixed and mobile, that is to say, only relatively fixed and relatively mobile, is the principle that aids the solution of several much-debated and certainly important questions of the Philosophy of the practical. And in the first place, the passions being understood as habits, the answer to the question as to whether or no they can be controlled, and if the answer be in the affirmative, then in what limits, receives a somewhat different meaning, which explains the interest which that question has always aroused. Nothing, in fact, removes our consciousness of freedom and personality in so brutal a manner and makes us feel our impotence and misery in so depressing a way, as to find ourselves with our good intention and action hardly begun, face to face with the unchained forces of our passions and of the habits that oppose it, which drown with their deafening clamour the weak and timid voice of the incipient action, vex it with their arrogance, and drag it along paths well known and abhorred. We fall then into mistrust and baseness, believe ourselves lost for ever; freedom and will seem to be fables for the adornment of sermons and the books of moralists. The sage who recalls to man the absolute empire that he possesses over his passions and exhorts him never to be troubled and to repeat the twenty or four-and-twenty letters of the alphabet, so that the spirit may have time to recuperate its strength, to resist and to conquer, seems to utter the insipid babble of one who has never truly loved and hated, and to measure the full and overflowing souls of others on the model of his own empty or almost empty soul. We laugh freely at the "short legs" of ideals and good intentions, and read again with satisfaction not