It would seem from this that Kant was bound to end in a renovated nominalism and mysticism, and indeed such is partly the case. Contemporaneously with him, Jacobi also observed the limit in which is enclosed the mechanical and determinist science of nature (the highest philosophic expression of which was then found in the _Ethic_ of Spinoza), since it works with the principle of causation and is impotent, unless it wishes to commit suicide, to leave the finite which it describes in a causal series, and Jacobi concluded in favour of mysticism and of _feeling,_ the organ of the Knowledge of God. Kant, like Jacobi, in his turn has recourse to the non-theoretic form of the spirit, to the practical reason and its postulates, to provide that certitude of God, of immortality, and of human freedom, which is not evident to the theoretic reason. But in Kant there are other positive elements which are not in Jacobi, and these elements, although not sufficiently elaborated by him and not harmonized with one another, confer upon his philosophy the value of a new Logic, more or less sketched. For he recognizes not only a theoretic but also a practical reason, which cannot be called simply practical, if it in any way produce (although only under the title of postulates), knowledge (and knowledge of supreme importance). He recognises also an æsthetic judgment, which, although developed without concepts, does not belong to the sphere of practical interests; and a teleological judgment, which is regulative and not constitutive, but not on this account arbitrary or without meaning. Finally, the very contradictions, in which the intellect becomes involved, when it wishes to apply the categories beyond experience, could not reasonably be considered by him to be mere errors, because they constitute serious problems, if the intellect becomes involved in them, not capriciously, but of _necessity._ All this presages the coming of a new Logic, which shall set in their places these scattered elements of truth and solve the contradictions. [Sidenote: _The a priori synthesis._] But the Kantian philosophy also contains, in addition to these elements and these stimulations, the concept of the new Logic in the _a priori_ synthesis. This synthesis is the unity of the necessary and the contingent, of concept and intuition, of thought and representation, and consequently is the pure concept, the _concrete_ universal. [Sidenote: _The intimate contradiction of Kant. Romantic principle and classical execution._]