Well, it has to be somewhat arbitrary. But it is nice that the relative minor of C, which is two steps down, is A. Otherwise you would have to go five steps up (from A to F, hypothetically, if A B C D E F G A were a major scale).
If C was called A, that wouldn't be particularly arbitrary.
It would certainly make more sense for people learning music. The C major scale is universally agreed to be the simplest, most basic scale, so wouldn't it make more sense for it to be ABCDEFG, rather than CDEFGAB?
No, because that's the A minor scale, which is the same notes as the C major scale but starting at A. A scale should logically always start with its root note.
That's not really what the comment is saying. If we relabeled the notes CDEFGAB to ABCDEFG, then ABCDEFG would be the "A major" scale under our new system. The question is, "Wouldn't that make more sense?" My answer is, "It would make a tiny bit more sense to the most absolute beginner students, who would then have to learn other scales anyway."
How does that make any sense at all? I don't see it making any more sense at all, not even a little bit. There's nothing arbitrary about C major/A minor being taught first as it's just the simplest scale with no sharps and flats. And calling a clearly minor scale major under a new system doesn't clear anything up for anyone.
The original question is frequently misinterpreted, so I can understand the confusion. I've seen the same question asked on forums a few times and someone always comes out of the woodwork saying that, "Well, ABCDEFG is a minor scale, not a major scale, what are you even going on about?" Let's ignore the part about why the scales we call C major / A minor being taught first, because we all agree that it makes sense to teach those scales first.
The question is, "Why are the notes labeled the way they are, instead of some different labeling (which would change their relationships between each other)?" This has nothing at all to do with "calling a clearly minor scale major". Let's suppose we relabel the notes, so that C is now named "A", D is now named "B", E is now named "C", et cetera. In this alternate universe, Ab is enharmonically equivalent to G, and the scale "ABCDEFGA" is a major scale, and "FGABCDEF" is the corresponding minor scale.
Part of the question is, "Why did we name the notes the way we do, instead of that other way?" That's actually an interesting question, once you get down to it.
Another part of the question is, "Isn't our system kind of arbitrary, and doesn't this alternative universe make more sense?" The answer is "No, the alternative universe isn't inherently better or less arbitrary, for the various reasons we talked about in this thread."
The main two reasons why we wouldn't prefer one universe over the other are because (1) both the Ionian and the Aeolian modes are important in western music, and it's difficult to claim that one is more important than the other, and (2) you have to learn a bunch of other scales anyway, and if you have a hard time with CDEFGABC then you're never going to make it through other basic scales like G major or F major.
(Bug... the "flat" symbol seems to be getting stripped out of my post... so forgive me for using "b" instead U+266D)
Ah, OK that's much clearer, I understand now. I'd say this, picking A for what is now C would be just as arbitrary as there is no "first" scale, they're all equally important and trying to match up a first scale to the first letter of the alphabet would be just as arbitrary. For those who feel the need to start with A, then start with minor scales, A minor first, artificial newbie weirdness solved.
Yes, exactly. I teach Music Technology, and that's one of the questions I get nearly every year, and one I've not found a concrete answer for, so I always preempt it by saying that the C is arbitrary as far as my research has gone.
It has to be somewhat arbitrary, because both the minor and major scales are common. Only 40% of popular music today is written in a major key.
Maybe, yes, you still learn the C scale first, but you'll learn the A scale the next week. In the grand scheme of things if you are having problems remembering the names of notes then moving the keys over two steps is not going to make the necessary difference.
The key of C is arbitrary (you could rename any of the other keys to C and rotate the whole system, and everything would work the same). But there's a case to be made that the diatonic major scale (Ionian mode) has a certain primacy in modern Western music, certainly more than say, Phrygian or Locrian. Both listeners and composers tend to hear the major scale as the most default, vanilla, un-surprising scale there is. It's one of the things that gives certain tunes like "Twinkle Twinkle Little Star" and "Happy Birthday" an almost annoyingly predictable quality. Even something pretty tame like Mixolydian sounds a little surprising compared to the major scale.
So it's legitimate to ask, if we're going to letter our notes based on the notes of one key, why not pick the key that sounds the most basic and fundamental? (The answer is that at one time folks heard music in a different way and Ionian didn't have the priority that it does now; see my other comment [1]). It also probably doesn't hurt that Aeolian (natural minor) is arguably the second most natural and "default" sounding mode, so it's not nearly as weird as if we decided to letter the notes off of Locrian or something.
