Law Professor Catherine MacKinnon. She's well known for her feminist take on legal issues, and she's just written a new book called "Only Words." (Harvard University Press) She argues that as long as sexual harassment, pornography and hate speech are protected by the First Amendment, equality will only be a word, not a reality. MacKinnon pioneered the legal claim for sexual harassment as a form of sex discrimination. She now teaches at the University of Michigan Law School.