A Doll's House is a work that signalled the end of traditional European theatrical drama in many ways, in large part due to its murky and ambiguous conclusion. Superficially, it seems that once her loan has been cancelled by the lawyer Krogstad, Nora Helmer has everything that she sought from the very start: an attentive and loving husband in Torvald, a relatively peaceful household where her children can be raised under the watchful eye of their nanny, and the elimination of the debt that she has owed since the early days of her marriage, with the promise that the unlawful forgery that accompanied the loan will be forgotten. But despite the fact that the main conflict is resolved by the play's end, the outcome is not a happy one. Nora leaves Torvald and the children: this in itself is indicative of a more serious problem than the existence of her debt, because if that were the only impediment to her happiness then its abolition would by logic result in a happier ending. It is evident then that Nora's dissatisfaction comes from somewhere deeper than the play's surface tension, perhaps finding an outlet in the way her notions of independence grow and change as the conflict evolves.
This underlying tension seems to be a result of contradictory elements in Nora's notion of how her husband ought to be dealing with her indiscretions. Her motive for illicitly acquiring a loan is clear: it is to save her husband's life when he is ill enough to need a holiday in a more temperate climate, but is too stubborn to pay for it himself. Because a woman in Ibsen's day was not permitted by law to take out a loan without her husband's consent, Nora was forced into using her father's name (and subsequently forging his signature) to fund the trip. Her justification for not having made Torvald pay for it himself was that "it would never have done for him to realize how ill he was" -- assuming that it was Nora's frivolity that warranted the holiday would be better for his health in the long run (160). In turn, she rationalises having kept the loan a secret by telling Mrs Linde that Torvald would "be terribly hurt and humiliated if he thought he owed everything" -- his good health and even his life -- to his wife (161). Both of these are reasonable excuses; and if this were the extent of the problem, it would seem obvious that Nora did what she did out of love for Torvald, and as soon as the loan was cleared up she could go back to simply loving him without complication.
Unfortunately for everyone involved, this does not seem to be the case. In keeping the loan a secret for fully eight years before she's found out, Nora gets a taste of independence, and this is where the most notable contradiction arises. Hiding the debt from Torvald, keeping as much spending money as possible and working in secret to cover loan payments, Nora is pleased by her autonomy: she remarks to Mrs Linde that "working and earning money" for herself is "almost like being a man", both halves of which are "tremendous fun" (162). But this independence is little more than a sham -- it is effectively countered by Nora's blithe assumption that should any problems arise between she and Krogstad, Torvald would happily shoulder the guilt and take care of the outstanding debt. She makes this clear to Krogstad, saying, "If my husband finds out [about the loan], naturally he'll pay you whatever I still owe, and then we'll have nothing more to do with you" (173).
Either tactic on its own would be an acceptable solution for Nora -- silently paying down the debt by herself, or confessing what she'd done to Torvald and letting him take care of its ramifications. Trying to have it both ways, however, leads to a curious dilemma: Nora seems to want her husband's support and protection, as she assures herself when speaking with Mrs Linde, but at the same time tries to avoid it by hiding her debt from him for as long as she can. The latter proves to be the side that wins out; when Torvald finds out about the loan, Nora even acts as though she resents his involvement, ordering him to let her retain the blame: "You shan't save me, Torvald! [...] You shan't take the blame -- I won't let you suffer for me" (220).
Why does this change come about when it does, and not earlier or later on? Krogstad's threats of blackmail are the catalyst -- presumably Nora had already considered both sides of her problem before expounding on it to Mrs Linde, but she had no reason to alter the status quo before it threatened to explode on someone else's terms. Mrs Linde's appearance is certainly another part of the reason; as a woman with neither husband to take care of her nor children to take care of, she is a sort of paragon of independence who can serve as a positive example for Nora, who seeks for a time to emulate her autonomy. It is telling that Nora's façade of independence disappears almost entirely once Mrs Linde and Krogstad come to realise that they need each other. What replaces it is a second contradiction, and the one that comes to shape the conclusion.
At the play's opening, Nora is seemingly content to be fawned over by Torvald -- he calls her his "little skylark", "little squirrel", "little featherbrain" (148), and she capers about childishly in ways that please him, just as a marionette or a doll in a doll's house acts (or performs, even) in accordance with the whims of its master. She does not seem displeased to have him as her protector, and in fact seems relieved that he is there to pick up the consequences should her own plans fall through: for example, speaking to Krogstad about the debt and his threat to reveal it to Torvald, she says to him sharply, "All right, then -- tell him! But it'll be the worse for you, because my husband will see what a brute you are, and then you'll certainly lose your post [at the bank which Torvald manages]" (172). But with Mrs Linde's arrival and Krogstad's blackmail to push her toward coming to her own independence, Nora's view of herself and her relationship with her husband changes -- she realises that it is hardly an equal relationship at all, and indeed that she and Torvald have "never [even] exchanged a serious word on any serious subject [...] never sat down in earnest together to get to the bottom of a single thing" (225).
This is the point at which things come to a head: Nora's desire to be protected from harm is counteracted by her longing for some sort of independence, however small. "I must stand on my own feet if I'm to get to know myself and the world outside," she tells him, "[t]hat's why I can't stay here with you any longer" (227) -- because to stay under his control would be to deny her status as "a human being" in her own right (228). When Torvald invokes her "most sacred duty" to her family as the reason that she must stay with him (227), she retorts by telling him of a duty that is even more sacred: her duty to discover and be faithful to herself, which is even more necessary than taking care of her family. In this way, A Doll's House is a study of opposites in subtext that cannot be resolved simply, or at all. Before she leaves for good, Nora tells Torvald that the only way she could stay is if both of them changed to the point that "[their] life together could be a real marriage" (232). "I don't believe in miracles any longer," she finishes -- and the door that slams shut as the play ends proves that Henrik Ibsen doesn't, either (232). The uncertainty of this conclusion, one where no-one at all wins, is as necessary as the conflict that precedes it -- if any lesson at all is to be extracted from it, perhaps it is that there are some problems and opposites that simply cannot be resolved.
Ibsen, Henrik. A Doll's House and Other Plays, trans. Peter Watts. London: Penguin Books, 1965.