Piano World Home Page Forums Our Most Popular Forums Composer's Lounge Why do "rules" exist?

Hi everyone. I'm new here. I'm calling myself BBB cause it stands for my three favorite styles, Baroque, Boogie and Blues, my personal three B's.

In preparation for further discussion, why do music theory rules exist? Is it that following the rules will simply make your music sound better? What does "better" actually mean? Who decided that they sound better, and why? (Better than what?)

I've answered these questions satisfactorily for myself and my own playing, but I was curious what others think. Particularly if there are any experienced, academic, etc. composers resident on this forum, or experienced self taught composers.

In another post, currawong wrote:



So, to me, this does not answer the question of "why" did music from the 18th century sound the way it did. I have an answer, but I wanted to see what others thought, first.

I think music theory is an attempt to make music intelligible. Though... I think music is mostly an emotional art, rather than an intellectual one.

"Besides being a sequence of the dreaded “consecutive fifths” (to be avoided like the plague in the best of posh Harmony circles)"

That's old school thinking. I love consecutive fifths. I use them regularly.

Best, John

P.S. I hope GS Monks doesn't see my reply.

Yes, as do I. I have a particular interest in imitating Baroque music, though, and when I do that, I do avoid parallel fifths. What I'm interested in is why did anyone ever avoid parallel fifths? In the context of other styles, as you rightly point out, they sound great! WHY did Bach avoid them? WHY did Mozart avoid them? WHY did Beethoven avoid them? Can anyone answer this?

One answer I've heard is that it is easier for a group of singers to follow their part if you avoid hollow consonant parallel movement such as fifths. That makes sense, but obviously the old composers were not composing just for voices nor were they constantly thinking: " now if someone transcribed this keyboard piece I'm writing for voice, I really hope it'd be easy for SATB singers to figure out their part!" There must have been another, simpler reason. What was it?

A youtube video: Why Parallel Fifths are bad This guy explains it with the "difficult for singing" perspective, but this is not enough for me.

Note that I consider this "parallel fifths" business only one part of the mystery of "WHY" did the old composers write that way. There are other mysteries. Why avoid augmented seconds? Why avoid doubling the leading tone? Again, I do have answers for these that satisfy me, and help me with my own creation of music, but I'm not certain how similar my own answers might be to those with "traditional" background in 18th century theory/harmony/composition.

The rules of harmony and music theory are similar to the rules of grammar in a language. A grammar textbook lists a few of the more common constructions in the language, but this barely scratches the surface of the language and the actual language is learned by using it in everyday situations. Similarly the rules in a music theory textbook are merely some of the more commonly-encountered constructions in music. Real music is infinitely more complex and is learned on the job, so to speak.

That still doesn't answer the "why." Imagine you are J.S. Bach himself, sitting down at a clavichord to create a new french suite movement. He improvises, he writes. He makes choices between different sounds. We know, from looking at his scores, that he chose to avoid parallel fifths. Does anybody know why? Why did he like that sound better? Is there an origin for this reason? *edited to remove content that did not advance my point*

Both the answer I originally quoted, and the one immediately prior to this post, basically treat music written by the old composers the same way science treats evidence in an experiment. "This happens a certain amount of the time, so we formulate a theory based upon it." The difference of course is that human response to sound is a complex mix of objectivity and subjectivity, and sorting out exactly what decisions the old composers made were subjective and which were objective can help to answer this mysterious question of "why" did they make the choices they did?

Another opinion (translated into my own words) is that it stops your chord progression from being a chord progression, and turns it into just a weird sliding double melody - the second chord doesn't really sound like a new chord, because of the way you got there. Now, if you WANT a weird sliding double melody because that's your style, go ahead. In baroque- & classical-style music, and anything where you are paying attention to counterpoint & voice leading including a lot of pop styles, you never want parallel fifths because they really do sound bad in those contexts. In the wrong context, they make you sound like a sloppy/lazy writer, or one who doesn't understand what he's doing.

The majority of rules in music are not really rules so much as "a useful checklist to make sure your music will sound good". (and "sound good to whom?" is always a good question)

Why? I think pretty soon I'll try to explain my own answer, so I don't end up sounding like a child asking why ad infinitum just for the joy of confounding others.

Don't think "rules". Think "descriptions of what has been found to work reliably in a given style". You don't need to rebel against them. Use them where they're useful.

Note that if you discard one set of conventions you'd better have an alternative set ready - complete anarchy doesn't make attractive music.

Good answer!

Alright...here's my personal answer. I'm not trying to say I've found some amazing thing that nobody else has understood before, clearly a lot of people understand it intuitively, I've simply chosen to try to answer this question verbally.

I think the simple reason for the old harmonic "rules" is that they loved the sound of thirds, and diatonic scales. Why did they love these sounds? From experimentation with temperaments other than equal temperament (on my clavichord), I can easily understand why they were fascinated with thirds. They have a very sweet sound, and standing on their own, especially on an instrument such as the clavichord which can produce a vibrato, they produce more pleasure than other sounds (on their own). Now, this is partly subjective, but the truth is the older temperaments did produce purer sounding thirds so it would be understandable if they wanted to emphasize the sound of thirds in their composition.

I think if someone asked me, I will play one of three sounds for you: a major third, a fifth, or an octave, which would you choose? For me, I'd choose the major third. And, I think a lot of people would also. This is perhaps not the best or only reason to make choices in composition, but it is an understandable one. For me, this answers the "why" for much of the old music. After all, in Bach's time people were still experimenting with temperaments for which ones produced sounds that were interesting on their own. 19th century and later, we had nothing but the piano and equal temperament so we stopped thinking about how to build beautiful sounding scales---and this informed our composition less. We stopped thinking (as often) in terms of how sweet sounding thirds are (and found many other interesting, and definitely beautiful sounds...I'm not saying later music isn't good...not at all)

I feel similarly about diatonic movement, but less so than the sound of thirds.

Another "why" I've tried to answer for myself is why you only ever find 6-3 chords in parallel movement in baroque music. To my knowledge, you rarely find 6-4 chords in parallel movement. The way I understand this, for myself, is that a 6-3 chord is a sixth on top of a third---thus we are "emphasizing thirds" (a sixth is an inversion of a third). a 6-4 chord is a sixth on top of a fourth---so the fourth produces a similar hollow sound to a fifth, and doesn't sound quite as good. It "de emphasizes" thirds.

One more interesting thing---I don't think I fully understood this until I got a clavichord for myself and played a lot on it. It makes the sweetness of thirds much more noticable than on the piano. In fact, equal temperament now sounds a bit harsh to me, as the thirds are very wide.

Sorry if that was a bit rambling...but the main point I'm trying to make is that---when I got a clavichord, I had the startling experience of it practically "teaching" me why the old composers wrote the way they did. The sound of the instrument revealed it in a way the piano never did, for me. And, I wasn't sure if anyone else might find reading about this experience interesting, and felt it wouldn't hurt to share.

One explanation which I've read (and which makes a lot of sense to me) has to do with overtone structures. Voices moving in parallel fifths or octaves tend to sound like one composite voice where the second or third partial of the lower voice is reinforced by the upper voice, similar to organ registrations. So a consecutive fifth or octave within a four-part framework might create the impression as if one voice suddenly dropped out. For Bach or Mozart, that would have been undesirable.

If, however, timbre (and that's what you're creating when you're reinforcing partials in such a way) is more important than classical, "proper" voiceleading, parallel intervals can make for interesting sound combinations.

I forgot to mention another "why" I answered for myself. Why not double the leading tone? Why not double the third in some cases? The reason, I think, is that the third tells you the most about what chord you are playing. Octaves and fifths tell you less, so doubling those notes sounds a bit better. I'm not trained in theory, so I'm actually not sure which ones are considered "best," but this vague idea has informed how I voice chords while improvising, and I've definitely noticed that certain doublings sound "bad," especially on the clavichord.

*edit*, I've also heard the "drop out" idea, and I think that makes sense also, and is related to what I wrote in the above paragraph.

Another way I like to think of it is: "keep triads complete, and don't over emphasize the important tones." This seems to produce beautiful voice leading much of the time.

After a quick googling, I found an explanation which confirms my own experience:

When to double tones...

This is interesting. The clavichord, the instrument which I'm claiming is helping me learn voice leading, has, I think, probably less "thick" timbre than other instruments. Thus, the hollowness of certain consonances stands out like a sore thumb. On the piano, a fifth sounds like a nice, thick, meaty sound. That said though, I do like to write music at the clavichord that follows none of these rules/guidelines--- But the "thirds sound really good!" idea seems to be the origin of all ideas which can make one's music sound baroque/classical. Works for me, anyway.

I'm in the thick of learning theory on my own but using books and there's also someone looking at it with me. We talk about this a lot. Some of music theory seems to describe what naturally happens, like saying "If you open your hand when holding a glass, the glass will fall and probably shatter." Other theory seems to describe conventions in music that got developed but which probably use the characteristics of sound (the dropped glass) in some way. Some of the rules are artificial and unrealistic: they simplify things to protect us or until we have more sophisticated skills and if we don't know that we can get boxed in. I'm discovering that some of the rules I learned earlier actually get broken later on - it was just a step. Thanks a lot! The most hilarious is when an example by Bach is followed by the admonishment to not break the rules that Bach did when writing like Bach.

About thirds: I found a used book written in the 1960's that wants to get past what theory usually does, so they have us explore things and listen. A first exercise is to distribute the notes of a triad in lots of different ways and write down what it makes you feel. Doubling the third might make it more cheery, having it mostly in the treble might lighten the mood. It's subjective. So that gave some insight.

Doubling a leading note confuses the movement, I think. There is another cool thing which is the tritone in the Dom7 (B and F). It's an aug4 or dim5 which is unstable and loves to resolve. At the same time you have two notes that are a semitone from their neighbor (B is the tendency tone moving to C, F moves to E) and that instantly gives the impression of the key.

Maybe the answer is to keep exploring those things and listening for the effect they seem to have. Also, that the rules are just guidelines and might even be wrong for some things.

I agree that choosing what sounds are better to you personally is definitely a subjective process. I think what I was getting at was, from the 1300's or so onward to Bach's time, people were experimenting a lot with temperament. In other words, what sort of scales, consonances, etc. sound good on their own before we've written a lot of music using them? I think that once they discovered that you could add thirds into the mix along with consonant fifths and octaves, they got fascinated with how "sweet" these sound. For me, the only explanation I need for the "why" of most music up to the 19th century is simply that they were fascinated with and emphasized the sound of thirds. Thus, as you say, these are not rules but guidelines for effecting a certain sound....I just call it "emphasis of thirds."

What is interesting is that---the process of "emphasizing thirds" is, to a degree, objective, but must start with the subjective: "I really like thirds" in order to be objective. For me, this clarifies all those mysteries. Before I had these realizations I thought that there was a possibility that all that theory was arbitrary. Now I realize it is only arbitrary once you reach the earliest, simplest reason for it all: thirds.

*edit* I want to also clarify that the existence of consonances is an objective observation, that I don't think anyone can deny. If you're playing with a string and making it vibrate at different ratios, you're bound to "discover" octaves, fifths, and thirds. Without composing any music...just those tones are much more pleasing than many of the wavering, sour, beat-ridden intervals between. So really---it was objectivity that started it all, subjectivity that got all the composition going (I really like this interval, the third, that I objectively observed in nature), and then objectivity that produced all of the theory thereafter---and then finally subjectivity once again that tore it all down.

But it all started with objective observations of nature.

Now that we use nothing but equal temperament and muddy the clarity of harmony with the piano---we are less inclined to think in terms of how sweet various consonances are and are more inclined to think in terms of melody and rhythm----which I am not denegrating at all, as there is a whole lot of modern music that I enjoy very much. But it is really satisfying to finally understand "the big picture" of it all...which is why I felt compelled to share. There is of course a possibility I've got it all wrong, but the answers I've come up with are more than enough for my own private music making.

edit: brief synopsis of the history of music:

(Greek times up to the gregorian chant monk guys)
objective: Ah, I've found octaves, and fifths! Oh, and thirds! Wow, those sound pretty (okay, that last sentence was not objective, but they found the thirds objectively while studying vibrating strings and such)

(medieval times to renaissance)
subjective: I REALLY love thirds, I'm going to write a gigantic pile of music that over emphasize them.

(baroque, classical, early romantic)
objective: Oops, my music didn't have thirds in as many places as possible. What are some guidelines I can follow to keep my beloved thirds singing beautifully throughout my composition? (result: baroque and classical music theory)

(late romantic to modern)
subjective: Temperament? What are you talking about? My piano tuner handles that. Thirds? Those are pretty cool, but I also love thick clusters of tones that have a really rich, lustrous timbre. (result: late romantic and modern music)

I don't think the idea of preferring thirds over fifths holds much water. I would really like to see some kind of evidence and not just speculation, before I would even think it worthy of discussion.

I'm with you buckaroo! I think the interval of a 5th (or even a flatted 5th) is much more appealing than that candy- a%# 3rd.

John

The history, when you get into it, is fascinating. There are so many twists and turns. I got my first foot in the door with "Music in the Western World: A History in Documents" which give snippets in time, including quotes from contemporaries. You see them enthusiastic, arguing, alarmed, outraged, intrigued at every point in history. They were upset when the chant had more than one voice because it was too carnal, upset when writing was invented because the mind would become lazy, upset at the strident violin, and we're still upset at new things today.

In regards to temperament, which is the tuning of the notes in the scale, we still use several temperaments today for instruments where the tuning can be controlled. This site does a good job of explaining several of them, and then showing when the musician might choose which in the fourth section. (go to "definition")
Violinmasterclass - intonation

Have you heard of the "barbershop fifth?" It uses the notes of the Dominant 7th, but tuned so purely that a fifth note is heard which isn't there, as though there were a fifth singer.

Rules of harmony don't actually exist universally but when you want to play a certain style of music that is within its own limits of playing then rules do exist, so harmony is a subjective matter.

There are no rules, and that's how geniuses came up with ideas, they didn't follow any standard conventions allowing them to do whatever they want. Sometimes composers would make up different scales allowing them to be original.

If you disregard any scales or music sounds you have heard before, and you experiment with the piano for a long time making up music without showing any influence, then you will eventually have a style that no one has ever heard before. Whether it would sound good or bad is a whole different story. When you do this, there are no rules and thus you are unlimited.


If you want to sound like Bach though, you must follow certain rules and limitations, or else you won't sound like him. You are limited at this stage.

Music is not always supposed to be good. Music is music and it is not necessarily good is sound and taste. Music today is becoming more and more diverse, and with such diversity there is diverse conventions, and it becomes harder to break those conventions and actually make good music. We've come to a point in history where our music will start to go bad and most people won't tolerate it anymore. We are coming to a point where we are finding music within the chromatics and the microtones, that is the serial techniques and chromatic scale and all the microtones, and within only those scales there isn't much good music, and the public today doesn't seem to care about microtonality and chromatic music.

Rereading: Actually I have not heard of emphasizing thirds. Each of the three notes of a chord has a role. The third determines whether the chord is major or minor and without it this remains ambiguous. Sometimes the third comes in later on or resonates from what was played before, so that you hear it in your mind even though it isn't there. Sometimes the ambiguity helps you do what you want to do with the music.