Mathematics is, as it were, a sensuous logic, and relates to philosophy as do the arts, music, and plastic art to poetry.

At a later period he was councillor of legation in the Austrian embassy at the Frankfurt diet but in 1818 he returned to Vienna. Schlegel et la genie du romantisme allemand (1904); by the same Erläuterungen In F. Culture et traduction dans l'Allemagne romantique: Herder Goethe Schlegel Novalis Humboldt Schleiermacher Hölderlin.

With his older brother August Wilhelm Schlegel he was a critical leader of German Romanticism.