"Dear Harriet, I give myself joy of this. It would have grieved me to lose your acquaintance, which must have been the consequence of your marrying Mr. Martin. While you were in the smallest degree wavering, I said nothing about it, because I would not influence; but it would have been the loss of a friend to me. I could not have visited Mrs. Robert Martin, of Abbey-Mill Farm."(chapter 7)

"What! think a farmer, (and with all his sense and all his merit Mr. Martin is nothing more,) a good match for my intimate friend! Not regret her leaving Highbury for the sake of marrying a man whom I could never admit as an acquaintance of my own!"(Chapter 8)

Why can Emma Woodhouse, Empress of Highbury, choose "the natural daughter of nobody knows who" with only looks & sweetness to recommend her as her intimate friend, but not admit an intelligent gentleman farmer as an acquaintance. I know that there were restrictions to violating the stratifications of social order, but the latter seems no more of a violation than the former. Is it that Emma has deluded herself that Harriet is actually the heroine of one of those novels & thus closer to being her social equal? Interesting that having no history benefits Harriet in Emma's eyes--she is a tabula rasa on whom Emma can write whatever she wants, and is moreover so malleable that she doesn't object to falling in with Miss Woodhouse's plans.