I've ceased listening in on his conversations with himself.
Oh, I'm still burning with curiosity every time I hear his muffled voice float up from some other part of the apartment, just loud enough for me to hear but not clear enough for me to make out the words.
What is he talking to himself about?
Is it about me?
Is it bad?

I've come to realize it's very rude to listen in on people's private conversations, especially with themselves. I came to that realization mostly because I recognize that I talk to myself as well.

And I would hate for him to hear what I have to say to myself.

So I think I'll afford him the same privacy.