Fanny Price is diffident about life at Portsmouth once she returns there. Jane Austen uses the occasion to reveal the nature of the character that had not been so completely revealed beforehand, perhaps because it would have been too unappealing to stay with, but now that the reader is so much invested in Fanny Price, Jane Austen can show just how singular that character is as well as how Fanny is, like most people, both possessed of insight and limited in her sense of what she wants her life to be like and how she is with other people.
Fanny finds her home at Portsmouth physically uncomfortable, and yet also recognizes the ways in which her family is like the family at Mansfield Park even if lacking their social graces. That recognition forces the reader of the novel to appreciate that morality is an individual characteristic and not just a social one, even if social graces are collectively a morality as well as an improved form of life because those graces do in fact make people more considerate of one another even if her mother is not particularly considerate. Her mother thinks that Mrs. Bertram must worry over the servant problem because that is her own problem of household management, while the truth of the matter is that Mrs. Bertram doesn't worry about the servants at all, because the servants do a better job on their own, since they are better selected and better paid, and because others in the family worry about them. Having servants is not a key to respectability at Mansfield Park. The family that owns it takes that for granted so that they can worry about other things that will establish themselves as of the sort of people they think they should be. But, on a personal level, Mrs. Bertram is not that much better than Fanny's mother. She may be kinder, but that is because she has time to be kinder, and her kindness means allowing Fanny to serve as a high level serving maid in recompense for her keep, as an expression of her gratitude. Mrs. Bertram is, if anything, more indolent than Mrs. Price, and is allowed to be so by her more comfortable social arrangements
But all of this Fanny could take in. What Fanny does not notice about herself is her indifference to her own family, which Jane Austen presents as the family's indifference to her. It is true that they do not present a very lavish table for her when she arrives, but then they have worked harder at doing something for her arrival than the Bertrams did for her when she arrived at Mansfield Park. And she expects them to treat her as a lady from Mansfield Park. But instead, her father settles in with his borrowed newspaper after the family has been more preoccupied with the concerns of William’s life than with what has happened in her’s, which is not surprising since he, after all, had been living with them, and his prompt arrival at his ship is something of an emergency. There is also the sense, however, that Fanny was always like this, that as a child she had also been aloof and removed, that she had occupied herself with her reading and separating herself from the rest of the family by going off to her little room in the same way she went off to her bigger room in Mansfield Park.
Susan, her sister, is the only person in the family in whom she takes an interest. She regales her with stories of Mansfield Park, recreating as best she can the world she inhabited in Mansfield Park, in her imagination, and living as she had when she was there. It is no wonder that the family seems to have little use for her as she lords it over them with her better ways. More important is that she has little feeling for them, makes little attempt to engage them or to appreciate them on their own level. She may reject Crawford and settle down with William in a brother and sister cottage, but she has no intention of either returning to Portsmouth as a way of life, or for that matter engaging in the London life of Henry Crawford, even if she is tempted to do so. Her success to this point has been created out of her firmness, apparent docility, and her ability to be alone and reserved, to gain life from her books and her general principles, and that is the way she intends to be.
That explains her response to Tom Bertram’s illness. She does not know whether to take an active role and request to be sent for so that she can return to Mansfield Park and comfort the family in its time of need. That would seem to be in her self interest as well as an expression of any feeling she has for the family. But she is remarkably reserved, and simply awaits news of what to do, appearing to modestly resist any temptation there is to step forward, lest it be construed as presumptuous, when in fact she has no great desire to express her feeling to anyone, nor such great regard for Tom that she feels obliged to his family to act as if she were properly a member of the family.
But since she does not know what would be appropriate in the matter, she terms her decision not to arrange for transportation back to Mansfield Park as allowing Sir Thomas Bertram to decide when he has need for her, as if she were indeed more a servant than a member of the family. This is the same principle she followed in the case of the play production, when she hesitated as long as possible and made no declaration of what should be done other than her own withdrawal from the activities. She did not feel it proper for her to take a role in deciding what to do, which was appropriate given her social circumstances at the time, but that is a cover, the reader can realize at this further state of the story, for her general passivity, her waiting for events to resolve her dilemmas, of both marriage and family obligations.
The idea of principle is therefore double edged. It means at first simply a generalization from experience about what to do under a set of circumstances, but it moves up into being a rule whereby one settles on what to do in circumstances which are ambiguous or unclear by making the empirical generalization serve as a matter of obligation. It appears to be like a moral rule, since it is what one does regardless of information, but it is still a scientific, utilitarian principle, because it is what one does as an application of past practice only because there is no information to clarify the situation. Morals are rules applied to limited information about self interest. This is a rather narrow and nasty understanding of non-utilitarian morality: it is inferior to utilitarian morality because it is merely a bad, rough calculation which will have to do, and yet it appears in the trappings of high moral language. And that is the way Fanny has conducted her entire life: she has used moral language because she has spend so much of her life in unfamiliar or only barely familiar settings that she has had to rely on general principles to give her a compass on how to behave. Categorical morality is the refuge of ignorance rather than the abandonment of self interest.
Tom’s illness seems to provide a way out of Fanny's overall dilemma. It is a deus ex machina which will resolve her problem, although not necessarily in a way she likes. It immediately occurs to the reader that should Tom die, Edmund will inherit Mansfield Park, and so be in a position to marry Mary, since his relative poverty is the only thing that makes Mary hesitate about a love match. That couples relation resolved, Fanny would have even more reason to accept Henry, for it would allow her to continue to live near Edmund, and persevere in the brother sister relationship that is one side of the ambiguous relationship she knows herself to have with Edmund, while having Henry as a perhaps unfaithful and absent and even possibly transformed husband who she could deal with as she pleased, since he would not be the center of her emotional life, unless she wanted to make him so. It would secure her future, allow her to move in any direction she wanted, while her present situation was fraught with danger because any of the options open to her-- continued association with Edmund, or even marriage with him, and the continued courting by Henry or even the good graces of the Bertrams, could be foreclosed by any number of events, including some simple insult she might pay the family inadvertently, since her connection to them is not legal but simply based on the favorable sentiments they have about her. Her situation is precarious, and Edmund's succession to Mansfield Park would move her in one direction.
Nor should such a possible resolution present a surprise to the reader, however unexpected the letter informing Fanny of Tom’s illness might be. The conventions of the Eighteenth Century novel, as well as the realities of Eighteenth Century life, remove characters from the scene through death all the time, or in some other way provide an external resolution, as when Tom Jones is found to be the illegitimate son but rightful heir of Squire Weston's sister.
But Jane Austen has already so well prepared the way for understanding that “Mansfield Park” is not a conventional novel in which all is made right in the world so that life is in accord with its natural scheme of inheritance and the social scale of being, so convinced has the reader become that people make the best they can of bad choices in which each choice has its appealing side, satisfying some self interest, even if no choice is a perfect one without problems, that the prospect of a deus ex machina comes as a disappointment from which one hopes Jane Austen will save us, which she does indeed do, but not before Fanny receives a letter from Mary which she finds proof positive of Mary's cynical and immoral nature because it is so candid about stating what is obvious about the change in Edmund's fortune.
The reader is less prepared to find Mary's letter so incriminating partly because she does no more than state what the reader has already been led to think about the matter. How could anyone deny Mary the right to have such thoughts? She would have been a fool not to see the possibilities, which are, after all, fully in accord with the morality of self interest which had been the hallmark of Mansfield. But Mary is so foolish as to state them, and to state them inelegantly, as a matter of personal greed, rather than as a matter of what the science of morality would dictate as appropriate under changed circumstances. First off, Mary, for all her graces, was not as clever as Fanny, and could hardly be expected to either find the right way to say something or decide to just say nothing at all. And, moreover, Mary had come to treat Fanny as a sister in the prospect of her becoming a sister-in-law, and so could confide in her more candidly than she would to someone else. After all, Fanny was at the moment confiding all sorts of things to Sally, who was her flesh and blood sister, but whom she had not seen for years and years. It may have been crude of Mary to say what she did, but Fanny is an unforgiving soul, especially of a woman who loves the man she loves.
But then another unexpected event enters the picture: the elopement of Maria with Henry. Again, Fanny remains in Portsmouth, passive, waiting for more information in correspondence from others rather than declaring herself or expressing concern or interest. Mary does not have Fanny to confide in, to perform the sisterly function that would be expected of someone else, but a role from which Fanny is exempt because she has for so long been the great stone face that she is expected to be someone on whom moral virtue is projected: what would she think were the right thing to do? Fanny is a kind of moral oracle who operates from afar, just as Sir Thomas had been, though not as well, from Antigua.
Instead, Mary confides in Edmund, who one would think would supply an attentive and sympathetic ear, since this is the woman he wishes to marry. Mary suggests that, proprieties aside, the interest of the combined families is to allow the couple to live together till they decide to marry. This is not an approval of the elopement but the common sense for which those at Mansfield Park are supposedly renowned. It would be far more a disaster for Maria to be disgraced permanently and for Henry to lose his marriage to Maria than for him to make an honest woman of Maria by becoming a reformed rake. If he were, after all, good enough to marry Fanny, then he certainly is good enough to marry Maria, who is now a fallen woman, and has shown poor judgment before.
Edmund greets this heartfelt confidence between a woman and the man who has expressed interest in marrying her by turning on her, by immediately interpreting this declaration of her’s as conclusive proof of her immorality. When he says as such, in no uncertain terms, she is clearly shocked, for she had been on the verge of accepting him, even though Tom's health had improved, and there would have been considerable sacrifice in the match for her. Her response is, quite correctly, to call him morally self-righteous, unwilling to consult normal moral concerns, and so she tells him to leave. When he does so, she hesitates and calls him back, but he is unwilling to return, which is the contempt he shows for a woman who is not only willing to face the fact of his poverty, but also swallow her pride so that she might marry a man she knows will never be candid with her.
The willingness of both Mary and Henry to marry their social inferiors requires explanation. Both of them, the reader has suspected and it now seems confirmed, are in as precarious a position as Fanny. They have been raised in a house not their own on the sufferance of people whose shortcoming they endure not from familial love but out of social necessity. They border themselves with the Grants for periods of long duration, in part out of what they declare is their sentimental attachment to the country, as well as because of their need to find someplace to live where they can be more than they are, and also out of a sincere admiration for what they see as the orderliness of life in Mansfield Park. But they have both been trained so long in their upbringing to a level of morality which is more candid and more acceptant of the vicissitudes of life that it is difficult for them to appreciate just how constricted are the moral concerns of the people at Mansfield, just how inhibited their language is. So while they are thought of as from a better class than those in Mansfield, and are perhaps therefore understandable as more sophisticated, this sophistication is not appreciated by the Mansfieldians when it has to do with anything of great consequence to them, and the Crawfords, for their part, think the good order of Mansfield does not mean that they cannot be candid when candor is required, as it is often enough in life. What seems eccentric about each party to the other becomes seen as essential to them in moments of crisis. This is a gap which is not easily breached.
Fanny had accepted just such condescension from the Mansfieldians. She had accepted that she needed to learn to behave in a different way than she had at Portsmouth, had accepted on faith that the manners of the richer were better than those of the poor, and yet neither she or Edmund would allow themselves to be tutored in the behavior of an even higher social class, but responded with a narrow mindedness that might have been expected of Mrs. Price. She had risen as far as she intended to in her vision of what a proper life amounts to. And so Fanny remains forever the Portsmouth girl who clings to her final prize, Edmund, because that is the only one she wanted. She was not taken in by wealth or manners, only by her own passions.