Wait...what?

That is how i felt after reading this, i'm sure many of the other people reading this did as well. The last 20 pages of white castle are confusing!

The mentioning of 'Fight Club' in class is now ringing true. I am interested, intrigued and confused. 

I assume things unfolded like this: Hoja became the Italian and lived his life as if he had just returned from enslavement. The italian became Hoja and worked for the sultan and Istanbul. Eventually the original Hoja wrote a book about 'the italian' (who he now 'is') and the original Italian wrote a book about 'Hoja' (who he now is). A fan of the original Hoja (new italian) visited him and learned from him. the fan then came to the Italian (new Hoja) and talked with him, but since the original italian is also the narrator he exposes the full truth and lets the visitor read the book. 

I'm guessing that last scene of the book the visitor flips back to the scene where Hoja and the Narrator swap and had to try and believe the story.