Indeed, in his autobiography, Mill claimed Harriet as the joint author of most of the books and articles published under his name. He added, "when two persons have their thoughts and speculations completely in common it is of little consequence, in respect of the question of originality, which of them holds the pen." The debate about the nature and extent of her collaboration is ongoing. Few of Mill's friends were permitted to meet her. Thomas and Jane Carlyle, who were allowed to make her acquaintance, did not form a favourable opinion of her abilities. Thomas Carlyle described her as “full of unwise intellect, asking and re-asking stupid questions”, while Jane considered her “A peculiarly affected and empty body".