Nietzsche's basic discovery is that consciously held convictions are rationalizions - they are employed by a deeper will to expand the aim of which is different from those authorized by the convictions. The ultimate conclusion is that Christian-derived values like equality and justice are both false and contingent, and they can and should be replaced by new ones - perhaps ones that are more brutal.
This thesis depends on a metaphysics of will to power, but this metaphysics is merely an hypothesis, derived from 19th century discoveries about energy and evolution. With a little more conceptual labor, we are able to arrive at a more profound philosophical insight: that any ontology is itself contingent and false, and that in human history there is a vector towards erosion of these as knowledge and technology improve. Hegel. But this thesis has a limit too. It cannot account for the progress of history or the existence of reason (except circularly), and it seems to foreclose access to certain truths available to higher states of consciousness.
It is here that music must take over from philosophy. Music at its best makes contact with something that simply cannot be expressed - neither aesthetically nor rationally. But it nevertheless has a great deal of quasi-articulable content.
So the passage from SHEYMN to YLYLCYN is accomplished by art, the passage from YLYLCYN to ANANON is accomplished by thought, and the passage from YLYLCYN to OIOION is accomplished by music.
But this is just the way -up-, the arrival at true freedom. From there we must travel back down. This is the work of perichoresis - passing from music, to thought, to art, and back to music.