"These books only record true history. They cannot be altered, cannot be destroyed. And even if they could, it would not change a thing in your world," The librarian answered. She shifted slightly, her anger mellowing a little. It never failed, there was always one who tried to destroy history, destroy knowledge. And she never trusted them.<br/><br/>She had, to her utter most horror, met Hitler; a man who had started a genocide against certain people and had tried to start that same genocide here. That had started with him trying to burn a few books.<br/><br/>"If you really wish to stop him, you will have to find another way to do it. These books hold no power over other worlds."