Philosophical Letters of Friedrich Schiller is great collection of philosophical works by the great German philosopher, Friedrich Schiller.

Johann Christoph Friedrich von Schiller¿November 1759 - 9 May 1805) was a German playwright, poet, and philosopher. During the last seventeen years of his life (1788-1805), Schiller developed a productive, if complicated, friendship with the already famous and influential Johann Wolfgang von Goethe. They frequently discussed issues concerning aesthetics, and Schiller encouraged Goethe to finish works that he had left as sketches. This relationship and these discussions led to a period now referred to as Weimar Classicism. They also worked together on Xenien, a collection of short satirical poems in which both Schiller and Goethe challenge opponents of their philosophical vision.

Schiller wrote many philosophical papers on ethics and aesthetics. He synthesized the thought of Immanuel Kant with the thought of the German idealist philosopher, Karl Leonhard Reinhold. He elaborated upon 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. The link between morality and aesthetics also occurs in Schiller's controversial poem, "Die Götter Griechenlandes" (The Gods of Greece). The "gods" in Schiller's poem are thought by modern scholars to represent moral and aesthetic values, which Schiller tied to Paganism and an idea of enchanted nature. In this respect, Schiller's aesthetic doctrine shows the influence of Christian theosophy.