"The Art of Fugue" (Die Kunst der Fuge), BWV 1080, is Johann Sebastian Bach's monumental unfinished work demonstrating the full range of fugal and canonic techniques, composed in the final years of his life (c. 1748–1750). Contrapunctus I is the opening piece, presenting the main subject in a straightforward four-voice fugue and serving as the foundation for all subsequent contrapunctal elaborations.
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Public Domain