Interesting article; you might want to also look into things like the physics of the harmonic series, and things like the changing significance of major/minor modes over time -- in Western music, the use of minor keys to denote sadness is a relatively recent development, which is why there's so much e.g. plainchant that sounds "sad" to modern ears despite having a happy topic).

And, of course, your definition of music might have a very different meaning to people who are Deaf or hearing-impaired! The ability to perceive differences in frequency (or pitch) is overwhelmingly common, but really not universal among humans.