The year 1815 saw the publication of Solger's principal work, _Erwin,_ a long philosophical dialogue on the beautiful; subsequently in 1819 he gave a course of lectures on Æsthetic which were published posthumously. He was one of those who found but a glimpse of truth in Kant and held the post-Kantians in very slight estimation, particularly Fichte; in Schelling, who begins from the original unity of the subjective and the objective, he detects for the first time a speculative principle not adequately developed, since Schelling had never triumphed dialectically over the difficulties of intellectual intuition.[33] [Sidenote: _Fancy and Imagination._] Solger was one of those who conceived of Imagination as totally distinct from Fancy: fancy (says he) belongs to common cognition and is none other than "the human consciousness, in so far as it continues, in temporal succession, infinitely reasserting an original intuition"; it presupposes the distinctions between common cognition, abstraction and judgement, concept and representation, amongst which "it acts as mediator by giving to the general concept the form of individual representation; and to the latter the form of a general concept; in this manner it has its being among the antitheses of the ordinary understanding." Imagination is totally different; proceeding "from the original unity of the antitheses in the Idea, it acts so that the elements in opposition, separated as they are from the idea, find themselves united in the reality; by its means we are capable of apprehending objects higher than those of common cognition and of recognizing in them the idea itself as real: also, in art, it is the faculty of transforming the idea into reality." It presents itself in three modes or degrees: as Imagination of the Imagination, which conceives the whole as idea, and activity as nothing more than the development of the idea in reality; as Sensibility of the Imagination, in so far as it expresses the life of the idea in the real and reduces the one to the other; lastly (and here we have the highest grade of artistic activity, corresponding with Dialectic in philosophy) as Intellect of the Imagination or artistic Dialectic, conceiving idea and reality in such a way that one passes over into the other, that is to say, into reality. Other divisions and subdivisions are made on which it is not necessary to dwell. Imagination is said to produce the Irony essential to true art: this is the Irony of Tieck and Novalis, of whom Solger is in a sense a follower.[34] [Sidenote: _Art, practice and religion._]