Anonymous IV
writer of a treatise of medieval music theory
Anonymous IV is the designation given to the writer of an important treatise of medieval music theory. He was probably an English student working at Notre Dame de Paris, most likely in the 1270s or 1280s. Nothing is known about his life. His writings survive in two partial copies from Bury St Edmunds; one from the 13th century, and one from the 14th.
Anonymous IV mentions Léonin and Pérotin as the best composers of organum and discant respectively. He also mentions specific compositions as being by Pérotin (or Perotinus), including the four-part organa quadrupla Viderunt and Sederunt. Anonymous IV also mentions the work of the theorist Franco of Cologne; describes organum, discantus, rhythmic modes, and genres of composition; and gives rules for the use of notation and of consonance and dissonance.
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