VI. The Age of Kant and Goethe
> In relation to the agreeable, to the good, to the perfect, man is only serious, but he plays with beauty. In this respect, to be sure, we must not think of the games that go on in real life and that ordinarily are concerned with material objects, but in real life we should also search in vain for the beauty that is meant here. The beauty existing in reality is on the same level as the play-impulse in the real world, but through the ideal of beauty, which is upheld by reason, an ideal is also demanded of the play-impulse that man is to consider wherever he plays. (Letter 15.)
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ENAP1973