I’ve always liked this quote… “Talking about music is like dancing about architecture” – Steve Martin.
When I think of a definition of music I think, “Music is comprised of rhythm, melody, harmony, and color”
I also like the article by Craig Morris called
Sound Sculpting that asks and answers your question about what music is.
I like this one too!
“My music is best understood by children and animals.” – Igor Stravinsky
And finally, related to that article about the “As SLow aS Possible” by John Cage:
“The principal of the endless melody is the perpetual becoming of a music that never had any reason for starting, any more than it had any reason for ending.” – Igor Stravinsky