
Fourth down the pile we come to a book by Marquis De Sade, who Paul sings about in hit single 'Legacy', the twelth track on the album - see the lyrics on the open book to the right of it. Second from bottom is 'The Book Of Mormon', which influenced Cancer ("My book of Mormon wrapped in Turin") in which Paul criticises Christianity (read the lyrics - their fab) suggesting Christians bend it's rules to live their lives however they want and that it only exists because people turn to it out of desperation. Finally bottom of the pile is 'The Bible Code', which probably also influenced Cancer, though it seems strangely ot of place (being modern and not anti-religious).
Notice there's another pile of books in the bottom right of the cover.