You have no idea where this beauty comes from and you know better than to think that such clarity could come from your own heart. Maybe, like Sparrow, Kai was terrified that one day the sound would shut off, his mind would go mute, and all the notes would disappear.
Yes, perhaps one day the sound will shut off, and I will not hear the music anymore; perhaps it will happen in a bookstore, or the library; perhaps it will happen when a well-meaning friend accosts me in the street, and shares with me a cherished verse, asks me for an opinion. I will hear or read the words, and nothing will come: no note of recognition, no quiet call to interpretation, no sudden connection. Will I then remember what is said here: that beauty comes, not from our own heart, but from another? And will I remember to come back to the things I have stored and hoarded, the fleeting records and fragments, like the bread crumbs strewn by Hansel to find a way home? Will I remember to come back here?