I don't know. I don't think books are harmful in and of themselves. They contain and put forth ideas that may not be good, yes, but the real trouble comes when evil sick people come along. They either twist the words to use them as an excuse to justify their evil (people do that with the Bible, it drives me crazy! cuz the Bible doesn't actually justify that stuff), or they will run with someone else's bad idea. Either way the trouble isn't so much with the book, but with the people who get their hands on it. And many of them would be doing that crap anyways even if they didn't have a book in their hands.