Why does Worlds of Music call this music programmatic, rather than abstract? According to Worlds of ...

This music is descriptive, that is, based on a story, in this case Rahim's being free like a wild horse. Abstract music, on the other hand, is not based on any extra-musical program, e.g., the traditional music of Egypt and the Levant the lands bordering on the East coast of the Mediterranean SeaLebanon, Syria, Jordan, and the Palestinian territories, which includes as its core, a canon of pieces inherited from the Ottoman Turkey. Such Turko-Arabic music is often abstract and identified only by the name of the piece's form and its mode (maqam) or, in some cases, is given an impressionistic title like Al-Shaghal (Obsession)
 Horses uses major/minor Western diatonic scales rather than Arab modes, which feature characteristic phrases and progressions, and in many cases quarter tones.
 There is emphasis is on virtuosity over emotionality (tarab), which can be heard in fast passages, Western-style scalar runs, harmonics, and arpeggios.
 The use of harmonics and arpeggios requires the player to exploit the upper range of the instrument, something not heard in traditional ud playing.
 Repetitive, sequential phrases combined with the use of arpeggios and sometimes chords suggests Western harmonic progressions not used in traditional Arab music.