Contrary motion with Bach?

Question

I've been transcribing some Bach Chorales and other works recently, and I realized that, while in general he does keep contrary motion between the the Soprano and Bass, he does break this part writing "rule" quite frequently. It seems he does this most commonly on the cadences. Why do music theory teachers stress how important this is when Bach breaks the rule all the time?

Answer 1

"....all the time." ???



Oblique and contrary motion are advised as methods of achieving voice idenity, as is the provision of an idiosyncratic rhythm for each part. That advice comes as a direct result of examination of the works of the great contrapuntists, past and present.



It is not a 'rule', and never has been, of course. It is advice from people who have generally done a lot more than copy out a few Bach chorales, though.



If you disagree with your teacher, go ahead with your 'new method' of achieving polyphonic interest.



The polytonal and atonal contrapuntal music of, e.g., Stravinsky is every bit as polyphonically notable as is that of Bach. Stravinsky, for reasons that should be obvious, also uses contrary and oblique motion as well as competing rhythms that contrast with each other. Audible differentiation between the various parts aids the listener in the quest for multi-tasking when listening.



When polyphonic music approaches a cadence, the voices generally begin to merge, to unify, and the 'advice' of composition teachers in this situation actually coincides with your 'discovery'. [You had that right, anyway!]



You appear to believe that you have done research that shows this advice to be nonsense.. I very much doubt that our best contrapuntists break what you imagine is a 'rule' - even 'much of the time'.

I totally refute your spectacular claim that Bach does it 'all the time'.



If you wish to write ineffective, dull polyphony, use similar motion and rhythmic unanimity.



Good luck, though. Your composition may well prove to be a new cure for insomnia!

Answer 2

1) It's not a "rule." The "rules" you learn in music theory class are mis-presented most of the time. They are not "rules" that composers follow, but rather they are statistical generalities based on studies made of composers' tendencies. The reason that we say "contrary motion is desirable" is precisely because Bach and other comon-practice era composers used contrary motion a lot. Unfortunately, these theoretical conclusions are called "rules" because, in the same breath that they are presented to the students, the students are asked to compose music imitating that particular style. So, all the "norms" of this kind of music become the "rules" that the students follow. If your theory class were focused on 1950s rock n' roll, the "rules" you'd learn would be completely different. Make sense?



2) Music theory teachers stress the importance of contrary motion (particularly between outer voices, if you have a 3+ voice texture) because it allows the listener to perceive the voices involved as maximally independent of each other.



Hope this helps!



[Someone above asked about parallel 4ths. Yes, 4ths and 5ths are inversions, but that doesn't mean they're interchangeable. The perfect 5th is a stable, consonant interval. In most cases, the perfect 4th is either a dissonant interval, or at least not a stable consonance (unless you're reading Hindemith...). Think about how often you have a 4th above the bass note of a chord. It is probably either a 4-3 suspension, or a 6/4 chord (and the 6 and 4 above the bass are dissonances 9 times out of 10). Parallel 4ths aren't prohibited because using them (between non-bass voices) is just about the only way that you can part-write a series of parallel 6/3 chords with nice voice-leading. You're in trouble if you have parallel fourths between the bass voice and another voice...but the problem is because you're going to be dealing with at least one 6/4 chord...and if you have parallel 4ths, that means you've used your (dissonant) 6/4 chords incorrectly.]

Answer 3

The way I learned it is that contrary motion is better than similar motion, similar motion is better than parallel motion, and oblique motion fits somewhere on the hierarchy, but I forget where. None of these were prohibited except parallel perfect intervals.



While we're on the subject, I never could understand why some textbooks prohibit parallel fifths but not parallel fourths. After all, isn't one the inversion of the other?



At least Bach was consistent. He wrote parallel fourths in #106, ms. 5; #183, ms. 1; and #285, ms. 9, but he also wrote parallel fifths in #37, ms. 3; #121, ms. 4; #244, ms. 8; and #288, ms. 1.



I was playing second violin in the b minor suite for flute and strings. When we were rehearsing the fugue, I noticed that I had parallel unisons with the viola.

I asked the conductor, "Aren't those parallel unisons?"

The conductor said "yes."

I asked, "But aren't parallel unisons forbidden?"

Again, the conductor said "yes."

I must have looked puzzled. The conductor said, "Bach just bent the rules, that's all."

Then he added, "All the composers bent the rules except Palestrina---boring!"

Answer 4

Because Bach does it so well!



And, if you want to break the rules, you have to understand the rules first. Seeing how Bach pretty much wrote the rules for the Common Practice Period, I think he can do what he wants.

Answer 5

It is good to learn the rules at first, but within the rules themselves it is said that the more parts you have, the more the rules can relax. Also, at the end of it all, you do whatever you want. Each composer had their favorite things they liked to do.

Answer 6

There's no rules to music...Do whatever you think sounds well...Music theory is extremely helpful but you shouldn't limit yourself to it..