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Al-Farabi divided Kitab al-Musiqa al-Kabir into two treatises.
The first treatise is composed of two parts; following the Aristotelian tradition, al-Farabi split his study of music into a theoretical and practical aspect:
The first part, which consists of two discourses, is an introduction which establishes the theoretical principles of music and investigation into how sound is generated.
The second part applies the theoretical principles established in the first part to the musical instruments that were in use during al-Farabi’s time, while also discussing musical intervals and different kinds of melodies.
The second treatise was intended to be a commentary to the thought of previous theorists of music, but it is not extant.