Tereza's perspective on her relationship with Tomas complicates the story told in Part I. Kundera makes Tereza just as sympathetic as Thomas; her heaviness seems noble and beautiful. Unlike Tomas, she takes everything in her life seriously, from sexuality to tiny, significant signs.
Tereza's heaviness of being causes her to suffer horribly; her mother's torments weigh heavily on Tereza, as does Tomas's infidelity. Still, the heaviness also allows Tereza to find meaning and beauty in her life, a benefit of heaviness the narrator posited in the opening of the novel. Tereza imbues coincidences with deep meaning. She believes, therefore, that each choice she makes is predestined. She suffers none of Tomas's indecision; while he agonizes over the multiplicity of choices and paths availabl e, she feels calmly confident that each choice she makes is the only possible one.
This second section of The Unbearable Lightness of Being suggests that perhaps lightness and heaviness are not polar opposites. Tomas and Tereza represent different sides of the dichotomy, but both are capable of feeling the pull of the other side, and hence fall in love. Tomas falls in love with Tereza partly because he wants to feel heaviness. Tereza learns some lightness from Tomas; this lightness causes her to risk her life for her country, and then leave Czechoslovakia abruptly, and to enjoy t he company, friendship and eroticism of her husband's mistress, Sabina.
Kundera associates the body with lightness, and the soul with heaviness. He associates Tereza with the soul—a fitting association, considering her identification as a heavy character. Indeed, the body repulses Tereza, and she tries to live entirely as a soul.
Part 2, in portraying the free Western world, contradicts assumptions that political freedom means automatic happiness for individuals. Politically free Switzerland, where Tomas and Tereza move, does not offer Tereza the communities of dissidents or journalists to which she belonged in Prague. The people she meets in Switzerland treat her badly—the magazine editor tells Tereza Prague's problems are no longer fashionable, for example.