The Art of Fugue
Contrapunctus XI, the conclusion of this quartet of double and triple fugues, is one of AOF’s great moments. This is a gigantic triple fugue tightly linked with Contrapunctus VIII.
In this fugue, Bach permutes the subjects of Contrapunctus VIII in three ways. First he inverts all three subjects. Second, he introduces them in a permuted order — subject 1 of Contrapunctus VIII becomes subject 2 here, 2 becomes 3, and 3 becomes 1. Here are the present subjects in the order they appear.
Finally, Bach also inverts all three of these subjects over the course of the fugue — recovering the subjects of Contrapunctus VIII and leading to six themes spinning around one another.
As with Contrapunctus VIII, Bach wastes little time in bringing in all his subjects. The second subject appears at 0:59, and the third at 3:15, about halfway through. The proportions of this fugue are thus almost identical to those of Contrapunctus VIII, and are arranged very differently from those of Contrapunctus XIV.=
This fugue recalls Contrapunctus III not only in its affekt but in the recurrence of a motive used in that fugue:
Does this fugue “carry the cross” in the manner of Canon 11 of BWV 1087? Both the gravity of this piece, as well as the references to it, musically and structurally, in the rest of cycle, suggest to me that Bach must have accorded it special prominence in his thinking. Though it is of huge proportions, it never reaches the glory of Contrapunctus XIV, rather being content to bruise itself in bizarre, remote chromaticisms, especially in the last two minutes. Though this fugue exceeds all others in AOF before it in scope, it would be a most unsettling conclusion to the cycle, had Bach chosen to end it here.