Bach’s Art of Fugue functions in many ways as an instrumental counterpoint to the B-minor Mass, his last vocal work of the late 1740s. It has aesthetically nothing in common with contrapuntal and fugal treatises, and it doesn’t want to be a theory textbook. It represents a very personal statement concerning the art of composition, a deliberate synthesis of theory and practice in Bach’s very own language. Ullrich Böhme, organist of the Thomaskirche in Leipzig, plays the autograph version on the historic Riepp organ in Ottobeuren.