The symbolists often share themes that parallel Schopenhauer's aesthetics and notions of will, fatality and unconscious forces. The symbolists often used themes of sex (often through the figure of the prostitute), the city, irrational phenomena (delirium, dreams, narcotics, alcohol), and sometimes a vaguely medieval setting. The tone of symbolism is highly variable, at times realistic, imaginative, ironic or detached, although on the whole the symbolists did not stress moral or ethical ideas. In poetry, the symbolist procedure—as typified by Paul Verlaine—was to use subtle suggestion instead of precise statement (rhetoric was banned) and to evoke moods and feelings by the magic of words and repeated sounds and the cadence of verse (musicality) and metrical innovation. Some symbolists explored the use of free verse. The use of leitmotifs, medieval settings and the notion of the complete work of art (blending music, visuals and language) in the works of the German composer Richard Wagner also had a profound impact on these writers.