In his pursuit of the phantom of a beauty, which is neither that of art nor of sensual pleasure, exempt alike from expression and from enjoyment, he became enveloped in inextricable contradictions. Little disposed as he was to let himself be carried away by the imagination, he expressed his contempt for philosopher-poets like Herder, and kept saying and unsaying, affirming and then immediately criticizing his own affirmations as to this mysterious beauty. The truth is that _this mystery is simply his own individual uncertainty before a problem which he could not solve_, owing to his having no clear idea of an activity of sentiment. Such an activity represented for him a logical contradiction. Such expressions as "necessary universal pleasure," "finality without the idea of end," are verbal proofs of his uncertainty. How was he to emerge from this uncertainty, this contradiction? He fell back upon the concept of a base of subjective finality as the base of the judgment of taste, that is of the subjective finality of nature by the judgment. But nothing can be known or disclosed to the object by means of this concept, which is indeterminate in itself and not adapted for knowledge. Its determining reason is perhaps situated in "the suprasensible substratum of humanity." Thus beauty becomes a symbol of morality. "The subjective principle alone, that is, the indeterminate idea of the suprasensible in us, can be indicated as the sole key to reveal this faculty, which remains unknown to us in its origin. Nothing but this principle can make that hidden faculty comprehensible." Kant had a tendency to mysticism, which this statement does not serve to conceal, but it was a mysticism without enthusiasm, a mysticism almost against the grain. His failure to penetrate thoroughly the nature of the aesthetic activity led him to see double and even triple, on several occasions. Art being unknown to him in its essential nature, he invents the functions of _space_ and _time_ and terms this _transcendental aesthetic_; he develops the theory of the imaginative beautifying of the intellectual concept by genius; he is finally forced to admit a mysterious power of feeling, intermediate between the theoretic and the practical activity. This power is cognoscitive and non-cognoscitive, moral and indifferent to morality, agreeable and yet detached from the pleasure of the senses. His successors hastened to make use of this mysterious power, for they were glad to be able to find some sort of justification for their bold speculations in the severe philosopher of Königsberg. In addition to Schelling and Hegel, for whom, as has been said, the _Critique of Judgment_ seemed the most important of the three Critiques, we must now mention the name of a poet who showed himself as great in philosophical as in aesthetic achievement.