Examines the role of secular music in trecento Tuscan society through visual, literary, and musical sources. Three frescoes depicting music-making are considered: Ambrogio Lorenzetti's Effects of Good Government in the City (1337-40), Bonamico Buffalmacco's Triumph of Death (1330-45), and Andrea Di Bonaiuto's Allegory of the Dominican Order (1366-68). The sociopolitical meaning of these frescoes is compared with Boccaccio's references to music in the Decameron. Common aspects of the frescoes and the Decameron include Aristotelian political philosophy, Dominican scholasticism, metaphorical and realistic portrayals of women, and narrative structures based on the model of the exemplum. These elements contributed to the formulation of trecento musical aesthetics. The music of Gherardello da Firenze, Lorenzo Masini, and Francesco Landini is analyzed with respect to this aesthetic. [RILM-abbrev]