Loved that book. The thought, well question; "What is quality?" has always stuck with me and has to have been 20 or 30 yrs since I read it last.
The "looking for the ghost.." thing really made me think, too. The trials and tribulations one goes through in their lives that alter them to a point that they find their present self completely different from a former self is a freaky thought.
A really weird book of sort of the same introspective nature (in this case forced by an outside entity) is the "
Jesus Incident" (the book has little to do or say about religion)
This book is so horrific at times you put it down and shudder and at other times will choke you up with the beauty of life. The premise is scfi but the underlying message is to learn friendSHIP, hardSHIP and worSHIP threw horrible cruelty and adversity. Ya know, all the fun stuff.