What lavalamp is trying to say is that people listen to music because it makes them feel good, but it's hard (or impossible) to explain why it makes one feel good. It is a subconscious thing; it happens in your neurons and you aren't aware of the pathways and the sequence of neuronal firings that causes it to happen.

Maybe someday we'll have a theory that makes it possible to take some information about you (anything from a 'psychological test' to a full-blown brain scan), a sample of music, and determine whether you will enjoy it or not.