[croddin]

This is equivalent to saying a C Major chord only exists in our brains since it isn't a note.

[beardyw]

Well if we get on to hearing, our ears do a lot better than our eyes. From the source entering into hole on either side of our head we can split the sound into a myriad of frequencies and gather a lot of information from it.

In a similar situation from a single point of light out eyes would say "sort of blue-ish". Most visible frequency information is ignored.

[o_nate]

It seems reasonable to me to say that soundwaves exist in the world, but music only exists in our brains. There is something added in our perception of the soundwaves that turns them into music.

[9rx]

Something exits in the world, it seems. Sound waves and music are merely our interpretation of it. Maybe what actually exists in the world is music, and sound waves are what our brain invents when the music is too complex for it to grasp?