It must not be overlooked that Schiller delivered a course of lectures on Æsthetic in Jena University in 1792, and that his writings on the subject intended for reviews were couched in a popular style: no less popular, in his own opinion, was the style of the book quoted above, which grew out of a series of letters actually sent to his patron the Duke of Holstein-Augustenburg. But the great work to be entitled _Rallias,_ which he intended writing upon Æsthetic, was never completed; the only fragments which have reached us are contained in the correspondence with Körner (1793-1794). From the discussions between the two friends we gather that Körner was not satisfied with Schiller's formula and desired something objective, something more precise, a positive characteristic of the beautiful: and one day Schiller told him that he had definitely discovered such a characteristic. But what it was that he had discovered we do not know; no mention of it occurs in any further document, and we are left in doubt as to whether we have lost an integral part of his thought or merely the momentary illusion of a discovery. [Sidenote: _Schiller's caution and the rashness of the Romanticists._] The uncertainty and vagueness of Schiller's theory seem almost a merit in contrast with that which followed. He had constituted himself guardian of the teaching of Kant and refused to abandon the realm of criticism; faithful disciple of his master, he conceived the third sphere not as real but as an ideal, a concept not constitutive but regulative, an imperative. "From transcendental motives, reason here demands that communion be established between formal and material activity; that is to say, there must be an activity of play, since the concept of humanity can be complete only by the union of reality with form, the accidental with the necessary, passivity with liberty. This demand must be made because reason, in conformity with her essence, aims at perfection and at sweeping away all obstacles; and every exclusive operation of one or other activity leaves humanity incomplete and confined within limits."[9] Schiller's thought, as it appears in his correspondence with Körner, has been well represented as follows:" The union of sensibility with liberty in the Beautiful, which does not actually take place but is supposed to do so, suggests to man an intuition of the union of these elements within himself: a union which does not take place actually but ought to do so."[10] The times which followed had no such nice scruples. Kant had given new vigour to the production of works on æsthetic, and, as in the days following Baumgarten, every new year saw a number of new treatises. It was the fashion. "Nothing swarms like æstheticians" (wrote Jean Paul Richter in 1804 when preparing his own book on the subject for publication): "it is rare for a youth who has paid his fees for a course of lectures on Æsthetic not to produce a book on some point of the science in the