PeterT--I knew you were just overgeneralizing to make a historical point, and I was just jumping on you because I am obsessive-compulsive about details--but now these people have gotten to the point where they want to know where the scale comes from-- from Neil Lowe "How the originator came up with these particular sounds for the notes of the scale is for more musicological-ly minded minds than mine to explain."

The secret answer is that the development of scales--and the assignment of pitch values to them, was a process that began a long time ago--with Pythagoras as far as our records show, (but I'll bet that he was just trying to straighten out some questions and problems that were floating around at the time)--

Basically, there are three perfect intervals the fourth(g-c) and the fifth(C-G), and the octave, and the descending minor third (c-am--which is "It's raining, its pouring) that seem natural to the voice--they tend to occur in some form in musical material from all cultures (though there is a scale in Arabic classical music that rather perversely eliminates the octave, and the Locrian mode has an augmented fifth rather than a perfect fifth)--the other notes in between, as well as whether there are other notes, and how many there should be, has been up for grabs--and to a surprising degree, still is--

The diatonic scale, the do re mi thing, was one of a bunch of church modes that have been used in western music since about the 8th century--those were based on the ancient greek modes--The actual pitches used for those notes weren't settled on til the times we mentioned above, when even temperament was introduced--but when the classical period began, Western composers began to work with the major and minor scales, exclusively--

Today, with the use of a lot of bent and twisted notes from Jazz, use of microtones, and even totally new scale systems, there is a lot of redefinition of what comprises a scale, and there are a number of composers who actually create new scales and pitch assignments for each composition--

As far as folk music goes, musicologists have always fought over what pitches were what--the early collectors of spirituals evened out the bent notes altogether--and ethnomusicolgists still like to discuss what that blue note is--and whether it is an ornament or a scale element--and don't even mention scales from eastern and middle Eastern music traditions!