I found asian philosophies very interesting in this regard. There is an interesting Hindu philosophy about 4 states - awake, sleep, dream and turiya. In below video, lecturer explained them very beautifully.

https://www.youtube.com/watch?v=eGKFTUuJppU

Also you might enjoy Gödel, Escher, Bach: an Eternal Golden Braid where author tried to explain self-referential systems.

If you pick up any interest in asian philosophies, try https://www.amazon.com/Who-Am-Sri-Ramana-Maharshi/dp/1537599... and https://www.amazon.com/I-Am-That-Nisargadatta-Maharaj/dp/089...