Having himself conquered the Kantian dialect and learned to write it, Schiller had little patience with those who supposed that philosophic truth could and should be set forth in the easy manner of a fireside yarn. It was to free his mind on this subject that he published, in one of the early numbers of the _Horen_, an essay 'On the Necessary Limits of the Beautiful'. Here the burden of his thought is that the philosopher, aiming at truth, must not yield to the seduction of trying to write beautifully. His concern is with fact and logic; imagination and feeling have no place in his domain. The lure of beauty may relax the mind and endanger truth, just as it may relax the will and endanger morality. This last thought contained the germ of his further essays, 'On the Dangers of Aesthetic Culture' and 'On the Moral Benefit of Aesthetic Culture'. These, however, are only an amplification of ideas contained in the 'Letters'.
There remain for consideration, to complete our survey of Schiller's philosophical writings, his short essay on Matthison's poems and his long disquisition upon 'Naive and Sentimental Poetry'. In the review he discusses the subject of landscape poetry, thus touching upon a question that had occupied Lessing in the 'Laokoön'. But instead of arguing like Lessing that detailed description of objects is necessarily out of place in poetry, Schiller defends it as capable in a high degree of giving pleasure. The poetic effectiveness of a description he finds to consist, first, in the truthfulness of the description; secondly, in its power, analogous to that of music, to excite vague emotion; and finally, in its power to awaken ideas by the law of association. He distinguishes between 'true' nature and 'actual' nature. We arrive at true nature when we take away from actual nature whatever is accidental, peculiar or unnecessary. This process is precisely what is described in one of the 'Kallias' letters as 'idealization'.
To idealize an object is, then, in Schiller's vocabulary, not to beautify it, or to make it in any way other than it is, but to portray the 'idea' of it, that is, its essential truth, apart from all that is accidental or individual. He lays down the general rule that poetry is only concerned with true (or ideal) nature in this sense; never with actual (or historical) nature. 'Every individual man', he declares, 'is by just so much less a man as he is an individual; every mode of feeling is by just so much less necessary and purely human as it is peculiar to a particular person. The grand style consists in the rejection of all that is accidental and the pure expression of the necessary.'