Listening to an exploration of the influence of Western baroque music on the Chinese court, I found myself wondering whether anyone knows why the pentatonic scale became so firmly embedded in oriental culture?
According to my inherited copy of the Oxford Companion to Music (1945) the pentatonic scale "suggests an instinctive acoustic sanction" (Scales 10) but although, AFAIK, the Chinese were nowhere near as mathematically advanced as the Arab or Indian nations, I wonder whether there was some mathematical support for adopting such a scale, passing as it does through the tonic, to mediant, then jumping to the dominant before continuing to the leading note?
The pentatonic, along with the standard diatonic and 12-tone scale (tuned in terms of fifths) are all 'pythagorian', in the sense that there are only two types of 'semitones'. I recall coming across this surfacing in indian music as well, though I can't quite remember where.
That's not much of an explanation, but it's one thing that popped into my head.