This article focuses on the place and importance of hymns to the Gods in Plato’s Laws. After examining the musical theories and practice exploited by Plato, his interests in Cretan, Spartan, and Athenian cities and culture, the survey presents the mission of the three lawgivers of the Cretan polis of Magnesia: the founding of a virtuous city. Since they realized that choral music is a paradigm in Greek paideia, these lawgivers fix some musical rules to compel the whole population to sing hymns to the Gods. Their legislation is very strict, to prevent amoral poets from corrupting the city by combining some harmful harmonies. Looking for the best musical forms, they define the different sorts of hymns: the paper scrutinizes that typology of songs. Finally, a semasiological and diachronic analysis of the family word of nomos sheds light on the polysemy of that concept intertwining geography, politics, legislation and music.
Keywords : Musicology, Hymnology, Politics, Legislation, Ethics