In A Doll's House how does the play reflect the human condition in the "wonderful" miracle Nora thought would happen?
In Nora we see humanity perfectly reflected: she is first and foremost a woman. As such, Nora feels the responsibility that falls on her shoulders to care and nurture her family; to be her husband's exemplary wife, as well as her children's best friend. Here comes her tragically-human flaw: Nora's flawed upbringing led her to believe that the way to do her job of nurturer and lover is by pretending to be someone that would please everyone, and not by being herself.
As a result, Nora incessantly seeks the attention that she feels she would receive by doing exactly as would please all others. In return, however, all she gets is to be treated like a plaything; like the plaything that she is acting out to be.
When it is time for Nora to test her worth as a woman, she does this by forging her father's signature in order to get a loan (from a man that works for her husband) and use the money for much-needed medical care for Torvald. Nora claims that, if her husband ever finds out, he would gladly forgive her miscue; after all, it was all made out of love. However, the fact that she continues to hide what she did tells of a very basic human condition: the fact that we only think that we know those who we love; that we really are not in control of anything regarding others, or ourselves. Whatever will be, will be.
The moment the truth is finally known, Nora's biggest nightmare comes true: she is not only insulted and unappreciated for what she had done, but she had become the "shame" of her husband. It is only after Torvald discovers that no consequences will come as a result of Nora's actions that he does a complete turn-around and pretends that nothing was said. He even has the gall to tell Nora that "she is forgiven" and that things will return to normal.
Here is the moment when Nora wishes for a "really great thing", or for a "miracle of miracles".
Ah, Torvald, the most wonderful thing of all would have to happen...[that] both you and I would have to be so changed that our life together would be a real wedlock. Good-bye.
Nora's human condition continues to manifest through her hopes, her fears, and the fact that nothing is final no matter how much we try to make things stay the way we want them to. She realizes that she had wasted years living a fake life, and pleasing a man that has never really grown out of his comfort zone. When she goes through her epiphany and makes her final decision, she does not even wait to hear Torvald's version of her dream. Her miracle is simply: they would either have to be born again and start over, or they would have to be completely new versions of themselves to tolerate a real marriage. There is no option here; that would never happen. Both, Torvald and Nora, lived their life hiding away emotionally from each other's true selves.