I have seen cards based on characters from a book or series of books, or books by a particular author. They are interesting and can be in ways useful. However, I am a bit nervous about using them, particularly when they are taken from authors who almost certainly would not have approved of that use of their works. I'm not talking about copyright violations, although that is an issue; I'm talking about authors who almost certainly would have had religious or moral objections to Tarot. Would it be right to appropriate an author's creations for something he would have disapproved of? At best it seems impolite.