 Great respect for Aristotle’s theory of demonstration led al-Fârâbî to attempt to fit any theoretical discipline in its framework, though some of them, such as music, do not exclusively rest on necessary and universal primary principles, as they also include principles derived from empirical observations (Miriam Galston, 2019). As music is dear to al-Fârâbî, it is in the first part of his Great Book on Music that we find the most extensive consideration of primary empirical principles and their derivation from careful examination of practice, i.e., in this case of musical performances.