Mystical Aesthetic, which makes of art the supreme function of the theoretic spirit, or, at least, a function superior to that of philosophy, becomes involved in inextricable difficulties. How could art ever be superior to philosophy, if philosophy make of art its object, that is to say, if it place art beneath itself, in order to analyse and define it? And what could this new knowledge be, supplied by art and by the aesthetic activity, appearing when the human spirit has come full circle, after it has imagined, perceived, thought, abstracted, calculated, and constructed the whole world of thought and history? As the result of those difficulties and contradictions, mystical Aesthetic itself also exhibits the tendency, either to surpass its boundary, or to sink below its proper level. The descent takes place when it falls back into agnosticism, affirming that art is art, that is, a spiritual form, altogether different from the others and ineffable; or worse, where it conceives art as a sort of repose or as a game; as though diversion could ever be a category and the spirit know repose! We find an attempt at overpassing its proper limit, when art is placed below philosophy, as inferior to it; but this overpassing remains a simple attempt, because the conception of art as instrument of universal truth is always firmly held; save that this instrument is declared less perfect and less efficacious than the philosophical instrument. Thus they fall back again into intellectualism from another side. These mistakes of mystical Aesthetic were manifested during the Romantic period in some celebrated paradoxes, such as those of _art as irony_ and of the _death of art_. They seemed calculated to drive philosophers to desperation as to the possibility of solving the problem of the nature of art, since every path of solution appeared closed. Indeed, whoever reads the aestheticians of the romantic period, feels strongly inclined to believe himself at the heart of the enquiry and to nourish a confident hope of immediate discovery of the truth. Above all, the affirmation of the theoretic nature of art, and of the difference between its cognitive method and that of science and of logic, is felt as a definite conquest, which can indeed be combined with other elements, but which must not in any case be allowed to slip between the fingers. And further, it is not true that all ways of solution are closed, or that all have been attempted. There is at least one still open that can be tried; and it is precisely that for which we resolutely declare ourselves: the Aesthetic of the pure intuition.