In the final chapter, we see Tomas and Tereza in the countryside, on the night before their death. They are living an altered lifestyle, quiet and peaceful. The government does not have as much control over the country as it does over the city, so their political worries seem less urgent. Tereza is happy because they are finally alone, and Tomas is finally all hers.
Tereza's dog Karenin develops a wound on his leg which turns out to be cancer. Tereza is heartbroken, and thinks how much she prefers animals to people. She considers various moments of mass cruelty to animals, some of which cruelties were institutionalized under the Soviet regime. "True human goodness, in all its purity and freedom, can come to the fore only ...towards those who are at its mercy: animals."
Arguing with Tomas over Karenin and finding a letter to Tomas in a woman's handwriting, Tereza reflects that she seems to love her dog better than her husband. With the dog, she expects nothing and feels no shame; Kundera speculates that an animal is closer to Adam than fallen man is, and that a dog was never expelled from Eden. Tereza and Tomas put Karenin to sleep after spending some final moments with him; Tereza thinks the dog is smiling. They bury Karenin.
Tereza has a dream in which Tomas is called to report to the local airfield, and then shot by three men who look like officials. His body shrinks into a small rabbit, which one of the men catches and gives to Tereza. She finds herself in Prague, and finds the house in which her parents once lived. All the while, she holds on to the rabbit and knows she can keep it forever.
Tomas tells Tereza he has been receiving letters from his son. Tereza watches him work and realizes how old he has grown, and suddenly feels guilty for everything she has put him through. She realizes she has forced him further and further away from his original life as a successful surgeon in Prague, just to make him prove he loves her. Tomas is now weak and old, like the rabbit from her dream.
A man hurts his arm while working, and Tomas relocates it for him. That night, in celebration, they all go out dancing. After they return home, Tereza confesses her guilty feelings to Tomas, who tells her that he is happy. Their room resembles the bedroom Tereza dreamed of as a child.
Kundera contrasts Tereza's emotions for Karenin with her feelings for Tomas. She consistently wonders at the selflessness of her love for an animal, and at the security and comfort she feels when with her dog. She feels infinitely more insecure and desperate in her love for Tomas. The contrasts illustrates the selfishness and neediness of human love; Tomas and Tereza, like many of the other characters in the novel, have been trying to reshape and recreate each other since the day they began living together.
In a sense, Tereza's reshaping of Tomas can be considered successful; now that he has grown old and is separated from the urban environment that made his womanizing possible, Tomas has been tamed, much like the rabbit in Tereza's dream. While Tomas has incorporated some of Tereza's heaviness, as evidenced by his return to Prague to join her, and his decision to give up womanizing, he has affected and changed her as well. The life Tomas and Tereza lead in the country is a life of lightness, almost irresponsibility; having given up their careers, the two play at farming and ignore the totalitarian regime that rules their country.
In the preceding chapter, Kundera divided people who need a public into four types: those who need a public of unknown eyes, those who need familiar eyes, those who want to be in the eyes of the person they love, and the dreamers who live to be seen by an imagined being. Kundera places both Tomas and Tereza in the third category, those who need to be seen by the beloved; in other words, through the course of their time together these two seeming opposites have come together.
Kundera ends The Unbearable Lightness of Being with a touching optimism. He introduces the concepts of perfect love and human goodness—happy concepts, although Kundera claims they exist only rarely, and then only in the love of human and animal. Also, we finally see Tereza and Tomas together in a perfectly serene moment. While the reader knows that the couple will die in the morning, the book ends with a moment in which they are happy together. By compromising they have tamed their imperfect love, and both Tomas and Tereza have found happiness.
Three of the four main characters in the novel have died, each according to the way he or she chose to live. Franz died a dreamer's death; Tereza and Tomas die together. The only character left living is Sabina. She has planned for her death to match her light lifestyle, and in the meantime corresponds with Tomas's son Simon. The reader is left to speculate about her last adventure.