There are no first principles in music. The harmonic series is relevant, but
you can't start from the harmonic series and find your way to Western classical music.It just doesn't work like that. Music could have gone in various directions, and Western music happened to pick the various directions it developed in, more or less arbitrarily.
They happen to emphasise a combination of parallel blocks and horizontal lines, and various quite complex kinds of motivic and structural elaboration and development.
Post-classical music - especially electronica - is much more focused on rhythm and timbre. It has more complex sounds and sound combinations and less complex structures.
There isn't much in the way of rhythm-and-timbre theory yet, but it's on its way and will be a thing within a few decades.
All of it is a mess because music has always been about styles, experiments, and conventions, and those have changed over time.
And it's also written from the musician's POV. Not a mathematician's POV. Or a dabbler's POV. Or a nerdy POV.
For example - sooner or later people get to transposing instruments and the obvious question is "Why would anyone sane do that?" And the answer is because it's convenient for the players.
That's it. That's the rationale. For all of it.
So while it's awkward and not very elegant, it has a kind of consistency that's somewhat useful across multiple styles.
It's impossibly hard to invent a system that is so much better for this that it's worth throwing the old system away. People keep trying and failing, because you can't just rationalise part of it, you have to improve all of it. And it's such a huge thing that's not a practical project.
So it persists - partly as a relic, partly as a developing system.
It just doesn't work like that. Music could have gone in various directions, and Western music happened to pick the various directions it developed in, more or less arbitrarily.
They happen to emphasise a combination of parallel blocks and horizontal lines, and various quite complex kinds of motivic and structural elaboration and development.
Post-classical music - especially electronica - is much more focused on rhythm and timbre. It has more complex sounds and sound combinations and less complex structures.
There isn't much in the way of rhythm-and-timbre theory yet, but it's on its way and will be a thing within a few decades.
All of it is a mess because music has always been about styles, experiments, and conventions, and those have changed over time.
And it's also written from the musician's POV. Not a mathematician's POV. Or a dabbler's POV. Or a nerdy POV.
For example - sooner or later people get to transposing instruments and the obvious question is "Why would anyone sane do that?" And the answer is because it's convenient for the players.
That's it. That's the rationale. For all of it.
So while it's awkward and not very elegant, it has a kind of consistency that's somewhat useful across multiple styles.
It's impossibly hard to invent a system that is so much better for this that it's worth throwing the old system away. People keep trying and failing, because you can't just rationalise part of it, you have to improve all of it. And it's such a huge thing that's not a practical project.
So it persists - partly as a relic, partly as a developing system.