Music Phenomenon/Knowledge/Clips/The Elusive Semitones

Mysterious and Elusive
It seems unacceptable that, in our day and age, the two semi-tones in diatonic scales should remain a mystery. Yet they do, as no one seems to know why they break the regularity of the scale.

60 seconds
Using only a few appropriate scales, and observing their impact on scale degrees, the problem is soon solved, precisely in under 60 seconds, according to this flash clip.

The Elusive Semitones

The Elusive Semitones [1MB]