Allow me to share extended quotes from two talented Wiki authors.
“He elaborated Christoph Martin Wieland’s concept of die schöne Seele (the beautiful soul), a human being whose emotions have been educated by reason, so that Pflicht und Neigung (duty and inclination) are no longer in conflict with one another; thus beauty, for Schiller, is not merely an aesthetic experience, but a moral one as well: the Good is the Beautiful. His philosophical work was also particularly concerned with the question of human freedom….the ability to defy one’s animal instincts, such as the drive for self-preservation, when, for example, someone willingly sacrifices themselves for conceptual ideals.”
The second is from the entry for Weimar Classicism:
“After Schiller’s death, the continuity of these objections partly elucidates the nature of Goethe’s ideas in art and how they intermingled with his scientific thinking as well, inasmuch as it gives coherence to Goethe’s work. Weimar Classicism may be seen as an attempt to reconcile—in “binary synthesis” — the vivid feeling emphasized by the Sturm und Drang movement with the clear thought emphasized by the Enlightenment, thus implying Weimar Classicism is intrinsically un-Platonic. On this Goethe remarked: ‘It is the combination of the Age of Enlightenment and Storm and Stress. The genius and the sentiment are combined into a harmonic existence in order to be complete, to reach the perfect and highest state.”