In order to save her husband's life, Nora, in A Doll's House, is required to loan money and, due to it being illegal for a married woman to borrow money without consent, she deceives Torvald by forging her father's signature and taking the loan illegally. Torvald thinks she inherited the money and never questions his "little spendthrift" regarding the money. The theme of deception is reinforced by reference to Nora's father and also society's perception of acceptable behavior. The sexist theme runs throughout, Nora's father being a contributor, despite not featuring in the play.
Nora and Torvald's first discussion about Nora's father revolves around his questionable dealings and poor handling of money. Nora wishes she could have inherited some of "Papa's" qualities but Torvald concentrates only on his ability to squander money. Torvald appears to "forgive" Nora for her spending habits and
One must take you as you are. It's in the blood. Yes, Nora, that sort of thing is hereditary."
It seems Nora is powerless to change perception although she has attempted to improve her family's circumstances but has had to lie and keep secrets. Deception on Nora's part is evident but Torvald is also deceiving himself. Nora tells Christine how her father died around the time of the loan so it was not necessary for her to admit her deceit.
Nora recognizes that she left her father's house only to be treated the same way in her husband's house. Her father treated her like a "doll-child" and between them
You and father have done me a great wrong. It is your fault that my life has come to nothing.
Having believed that Torvald would understand Nora's motives, the plot is further developed as it has become clear to Nora that each generation is the same. The male-dominated society where appearances are everything has prevented her from developing any personality of her own. Even her ideas, if they differed from her father, were stifled and the same with her husband. Nora can only hope for some sense of individuality if she leaves her husband and children.