 From the fifteenth century, writers on music begin to elaborate on the aesthetic aspects of musical experience. The theorist and composer Johannes Tinctoris (c. 1435–1511) exemplifies various aspects of this new outlook on music. He defines harmony and consonance in terms of their appearance to the listener, rather than through mathematical notions. Harmony is thus described as the pleasing effect produced by sounds, whereas consonance and dissonance are respectively characterized as combinations of sounds that bring sweetness to the ear or hurt it (Liber de arte contrapuncti, chapter 2). In his Complexus effectuum musices, Tinctoris lists prominent effects of music, most of which involve emotional arousal, while the dedication of his Proportionale Musices refers back to Antiquity and the alleged emotional potency of its music.