In this dialogue, Coelho talks openly and honestly about his Catholic-Jesuit upbringing, his experiences of a mental hospital, prison, torture, black magic, and drugs before his conversion back to a Catholic spiritual tradition. He also speaks freely on more abstract concepts: politics, nationality, his understanding of 'the feminine', and what it means for him to be a writer.
What I especially appreciated about this book was the style in which it is written. It is clearly a conversation between two deep thinkers, and it was nice to have Coelho's own words in print, rather than it all being paraphrased by the author. Although I have to say that Arias played his role as interviewer very well - he doesn't dominate the conversation, but nor does he let Coelho do all the talking.
The reason I give this 4 stars rather than 5 is that there were a number of times when I would have liked Coelho to elaborate on certain points. Sometimes this was because I found a thread interesting and I wished he had run with it for a little longer; other times it was simply for the sake of clarity.
(Finally, I should just note that I read an English translation of the book and not the original Spanish version. There is at least one available in Australia, not sure about other countries.)