George Bernard Shaw (whose plays have been banned from a fair number of libraries) asked in Saint Joan, "Must then a Christ perish in torment in every age to save those who have no imagination?"

These, the books you're talking about here, are the ones that trigger our imagination to perceive the humanity of those whom others would rather dismiss. Until we can look--with the eyes of our imagination--into their eyes, we are limited in the ability to experience our own humanity.